Z calibration (#31)

* extras: Add automatic z calibration extension

Signed-off-by: Titus Meyer <tm@protoloft.org>

* add danger icons

* update to latest protoloft/klipper_z_calibration (2eb689b)

* update to latest protoloft/klipper_z_calibration (e1755d8)

---------

Signed-off-by: Titus Meyer <tm@protoloft.org>
Co-authored-by: Titus Meyer <tm@protoloft.org>
Co-authored-by: Rogerio Goncalves <rogerlz@gmail.com>

docs/Config_Reference.md

@@ -2104,6 +2104,89 @@ calibrate_y: 112.5
 #   be near the center of the bed
 ```
 
+### ⚠️ [z_calibration]
+
+Automatic Z offset calibration. One may define this section if the printer
+is able to calibrate the nozzle's offset automatically. See
+[Z-Calibration guide](Z_Calibration.md) and
+[command reference](G-Codes.md#automatic-z-offset-calibration) for further
+information.
+
+```
+[z_calibration]
+nozzle_xy_position:
+#   A X, Y coordinate (e.g. 100,100) of the nozzle, clicking on the Z endstop.
+switch_xy_position:
+#   A X, Y coordinate (e.g. 100,100) of the probe's switch body, clicking on
+#   the Z endstop.
+bed_xy_position: default from relative_reference_index of bed_mesh
+#   a X, Y coordinate (e.g. 100,100) where the print surface (e.g. the center
+#   point) is probed. These coordinates will be adapted by the
+#   probe's X and Y offsets. The default is the relative_reference_index
+#   of the configured bed_mesh, if configured. It's possible to change the relative
+#   reference index at runtime or use the GCode argument BED_POSITION of CALIBRATE_Z.
+switch_offset:
+#   The trigger point offset of the used mag-probe switch.
+#   Larger values will position the nozzle closer to the bed.
+#   This needs to be find out manually. More on this later
+#   in this section..
+max_deviation: 1.0
+#   The maximum allowed deviation of the calculated offset.
+#   If the offset exceeds this value, it will stop!
+#   The default is 1.0 mm.
+samples: default from "probe:samples" section
+#   The number of times to probe each point. The probed z-values
+#   will be averaged. The default is from the probe's configuration.
+samples_tolerance: default from "probe:samples_tolerance" section
+#   The maximum Z distance (in mm) that a sample may differ from other
+#   samples. The default is from the probe's configuration.
+samples_tolerance_retries: default from "probe:samples_tolerance_retries" section
+#   The number of times to retry if a sample is found that exceeds
+#   samples_tolerance. The default is from the probe's configuration.
+samples_result: default from "probe:samples_result" section
+#   The calculation method when sampling more than once - either
+#   "median" or "average". The default is from the probe's configuration.
+clearance: 2 * z_offset from the "probe:z_offset" section
+#   The distance in mm to move up before moving to the next
+#   position. The default is two times the z_offset from the probe's
+#   configuration.
+position_min: default from "stepper_z:position_min" section.
+#   Minimum valid distance (in mm) used for probing move. The
+#   default is from the Z rail configuration.
+speed: 50
+#   The moving speed in X and Y. The default is 50 mm/s.
+lift_speed: default from "probe:lift_speed" section
+#   Speed (in mm/s) of the Z axis when lifting the probe between
+#   samples and clearance moves. The default is from the probe's
+#   configuration.
+probing_speed: default from "stepper_z:homing_speed" section.
+#   The fast probing speed (in mm/s) used, when probing_first_fast
+#   is activated. The default is from the Z rail configuration.
+probing_second_speed: default from "stepper_z:second_homing_speed" section.
+#   The slower speed (in mm/s) for probing the recorded samples.
+#   The default is second_homing_speed of the Z rail configuration.
+probing_retract_dist: default from "stepper_z:homing_retract_dist" section.
+#   Distance to retract (in mm) before probing the next sample.
+#   The default is homing_retract_dist from the Z rail configuration.
+probing_first_fast: false
+#   If true, the first probing is done faster by the probing speed.
+#   This is to get faster down and the result is not recorded as a
+#   probing sample. The default is false.
+start_gcode:
+#   A list of G-Code commands to execute prior to each calibration command.
+#   See docs/Command_Templates.md for G-Code format. This can be used to
+#   attach the probe.
+before_switch_gcode:
+#   A list of G-Code commands to execute prior to each probing on the
+#   mag-probe. See docs/Command_Templates.md for G-Code format. This can be
+#   used to attach the probe after probing on the nozzle and before probing
+#   on the mag-probe.
+end_gcode:
+#   A list of G-Code commands to execute after each calibration command.
+#   See docs/Command_Templates.md for G-Code format. This can be used to
+#   detach the probe afterwards.
+```
+
 ## Additional stepper motors and extruders
 
 ### [stepper_z1]

docs/G-Codes.md

@@ -1212,7 +1212,7 @@ profile matching the supplied name from persistent memory. Note that
 after SAVE or REMOVE operations have been run the SAVE_CONFIG gcode
 must be run to make the changes to persistent memory permanent.
 
-### [smart_effector]
+### ⚠️ [smart_effector]
 
 Several commands are available when a
 [smart_effector config section](Config_Reference.md#smart_effector) is enabled.
@@ -1397,6 +1397,22 @@ the config. `REF_TEMP` manually overrides the reference temperature typically
 set during homing (for use in e.g. non-standard homing routines) - will be reset
 automatically upon homing.
 
+### ⚠️ [z_calibration]
+
+The following commands are available when a
+[z_calibration config section](Config_Reference.md#z_calibration) is enabled
+(also see the [Z-Calibration guide](Z_Calibration.md)):
+- `CALIBRATE_Z`: This calibrates the current offset between the nozzle and
+  the print surface.
+- `PROBE_Z_ACCURACY [PROBE_SPEED=<mm/s>] [LIFT_SPEED=<mm/s>] [SAMPLES=<count>]
+  [SAMPLE_RETRACT_DIST=<mm>]`: Calculate the maximum, minimum,
+  average, median, and standard deviation of multiple probe
+  samples. By default, 10 SAMPLES are taken. Otherwise the optional
+  parameters default to their equivalent setting in the z_calibration or probe
+  config section.
+*Note* that appropriate macros and/or configurations are needed to attach
+and detach a mag-probe for these commands!
+
 ### [z_tilt]
 
 The following commands are available when the