Joint3D: Remove utility method bindings for angular limits

The inspector now supports converting degrees to radians automatically when
using the `radians` hint, so all those utility bindings were redundant.

This cleans things up by making these properties with slash properly bound
to `set_param`/`get_param` which the users can call with the relevant enum.

doc/classes/ConeTwistJoint3D.xml

@@ -36,13 +36,13 @@
 		<member name="softness" type="float" setter="set_param" getter="get_param" default="0.8">
 			The ease with which the joint starts to twist. If it's too low, it takes more force to start twisting the joint.
 		</member>
-		<member name="swing_span" type="float" setter="_set_swing_span" getter="_get_swing_span" default="45.0">
+		<member name="swing_span" type="float" setter="set_param" getter="get_param" default="0.785398">
 			Swing is rotation from side to side, around the axis perpendicular to the twist axis.
 			The swing span defines, how much rotation will not get corrected along the swing axis.
 			Could be defined as looseness in the [ConeTwistJoint3D].
 			If below 0.05, this behavior is locked.
 		</member>
-		<member name="twist_span" type="float" setter="_set_twist_span" getter="_get_twist_span" default="180.0">
+		<member name="twist_span" type="float" setter="set_param" getter="get_param" default="3.14159">
 			Twist is the rotation around the twist axis, this value defined how far the joint can twist.
 			Twist is locked if below 0.05.
 		</member>

doc/classes/Generic6DOFJoint3D.xml

@@ -102,7 +102,7 @@
 		<member name="angular_limit_x/force_limit" type="float" setter="set_param_x" getter="get_param_x" default="0.0">
 			The maximum amount of force that can occur, when rotating around the X axis.
 		</member>
-		<member name="angular_limit_x/lower_angle" type="float" setter="_set_angular_lo_limit_x" getter="_get_angular_lo_limit_x" default="0.0">
+		<member name="angular_limit_x/lower_angle" type="float" setter="set_param_x" getter="get_param_x" default="0.0">
 			The minimum rotation in negative direction to break loose and rotate around the X axis.
 		</member>
 		<member name="angular_limit_x/restitution" type="float" setter="set_param_x" getter="get_param_x" default="0.0">
@@ -111,7 +111,7 @@
 		<member name="angular_limit_x/softness" type="float" setter="set_param_x" getter="get_param_x" default="0.5">
 			The speed of all rotations across the X axis.
 		</member>
-		<member name="angular_limit_x/upper_angle" type="float" setter="_set_angular_hi_limit_x" getter="_get_angular_hi_limit_x" default="0.0">
+		<member name="angular_limit_x/upper_angle" type="float" setter="set_param_x" getter="get_param_x" default="0.0">
 			The minimum rotation in positive direction to break loose and rotate around the X axis.
 		</member>
 		<member name="angular_limit_y/damping" type="float" setter="set_param_y" getter="get_param_y" default="1.0">
@@ -126,7 +126,7 @@
 		<member name="angular_limit_y/force_limit" type="float" setter="set_param_y" getter="get_param_y" default="0.0">
 			The maximum amount of force that can occur, when rotating around the Y axis.
 		</member>
-		<member name="angular_limit_y/lower_angle" type="float" setter="_set_angular_lo_limit_y" getter="_get_angular_lo_limit_y" default="0.0">
+		<member name="angular_limit_y/lower_angle" type="float" setter="set_param_y" getter="get_param_y" default="0.0">
 			The minimum rotation in negative direction to break loose and rotate around the Y axis.
 		</member>
 		<member name="angular_limit_y/restitution" type="float" setter="set_param_y" getter="get_param_y" default="0.0">
@@ -135,7 +135,7 @@
 		<member name="angular_limit_y/softness" type="float" setter="set_param_y" getter="get_param_y" default="0.5">
 			The speed of all rotations across the Y axis.
 		</member>
-		<member name="angular_limit_y/upper_angle" type="float" setter="_set_angular_hi_limit_y" getter="_get_angular_hi_limit_y" default="0.0">
+		<member name="angular_limit_y/upper_angle" type="float" setter="set_param_y" getter="get_param_y" default="0.0">
 			The minimum rotation in positive direction to break loose and rotate around the Y axis.
 		</member>
 		<member name="angular_limit_z/damping" type="float" setter="set_param_z" getter="get_param_z" default="1.0">
@@ -150,7 +150,7 @@
 		<member name="angular_limit_z/force_limit" type="float" setter="set_param_z" getter="get_param_z" default="0.0">
 			The maximum amount of force that can occur, when rotating around the Z axis.
 		</member>
-		<member name="angular_limit_z/lower_angle" type="float" setter="_set_angular_lo_limit_z" getter="_get_angular_lo_limit_z" default="0.0">
+		<member name="angular_limit_z/lower_angle" type="float" setter="set_param_z" getter="get_param_z" default="0.0">
 			The minimum rotation in negative direction to break loose and rotate around the Z axis.
 		</member>
 		<member name="angular_limit_z/restitution" type="float" setter="set_param_z" getter="get_param_z" default="0.0">
@@ -159,7 +159,7 @@
 		<member name="angular_limit_z/softness" type="float" setter="set_param_z" getter="get_param_z" default="0.5">
 			The speed of all rotations across the Z axis.
 		</member>
-		<member name="angular_limit_z/upper_angle" type="float" setter="_set_angular_hi_limit_z" getter="_get_angular_hi_limit_z" default="0.0">
+		<member name="angular_limit_z/upper_angle" type="float" setter="set_param_z" getter="get_param_z" default="0.0">
 			The minimum rotation in positive direction to break loose and rotate around the Z axis.
 		</member>
 		<member name="angular_motor_x/enabled" type="bool" setter="set_flag_x" getter="get_flag_x" default="false">

doc/classes/HingeJoint3D.xml

@@ -47,15 +47,15 @@
 		<member name="angular_limit/enable" type="bool" setter="set_flag" getter="get_flag" default="false">
 			If [code]true[/code], the hinges maximum and minimum rotation, defined by [member angular_limit/lower] and [member angular_limit/upper] has effects.
 		</member>
-		<member name="angular_limit/lower" type="float" setter="_set_lower_limit" getter="_get_lower_limit" default="-90.0">
+		<member name="angular_limit/lower" type="float" setter="set_param" getter="get_param" default="-1.5708">
 			The minimum rotation. Only active if [member angular_limit/enable] is [code]true[/code].
 		</member>
 		<member name="angular_limit/relaxation" type="float" setter="set_param" getter="get_param" default="1.0">
 			The lower this value, the more the rotation gets slowed down.
 		</member>
 		<member name="angular_limit/softness" type="float" setter="set_param" getter="get_param" default="0.9">
 		</member>
-		<member name="angular_limit/upper" type="float" setter="_set_upper_limit" getter="_get_upper_limit" default="90.0">
+		<member name="angular_limit/upper" type="float" setter="set_param" getter="get_param" default="1.5708">
 			The maximum rotation. Only active if [member angular_limit/enable] is [code]true[/code].
 		</member>
 		<member name="motor/enable" type="bool" setter="set_flag" getter="get_flag" default="false">

doc/classes/SliderJoint3D.xml

@@ -28,7 +28,7 @@
 			The amount of damping of the rotation when the limit is surpassed.
 			A lower damping value allows a rotation initiated by body A to travel to body B slower.
 		</member>
-		<member name="angular_limit/lower_angle" type="float" setter="_set_lower_limit_angular" getter="_get_lower_limit_angular" default="0.0">
+		<member name="angular_limit/lower_angle" type="float" setter="set_param" getter="get_param" default="0.0">
 			The lower limit of rotation in the slider.
 		</member>
 		<member name="angular_limit/restitution" type="float" setter="set_param" getter="get_param" default="0.7">
@@ -39,7 +39,7 @@
 			A factor applied to the all rotation once the limit is surpassed.
 			Makes all rotation slower when between 0 and 1.
 		</member>
-		<member name="angular_limit/upper_angle" type="float" setter="_set_upper_limit_angular" getter="_get_upper_limit_angular" default="0.0">
+		<member name="angular_limit/upper_angle" type="float" setter="set_param" getter="get_param" default="0.0">
 			The upper limit of rotation in the slider.
 		</member>
 		<member name="angular_motion/damping" type="float" setter="set_param" getter="get_param" default="1.0">