Fix issues #3, #4, #5

The unnecessary dependency from the files in the addon to the example directory have been removed. The example directory should always be able to be removed without impacting the use of the plugin. This closes issue #3.

The head and tail can now adjust the segment so that the head and/or tail can be centered on the spot, instead of just being before or after the spot. This can give a better looking arrowhead. This closes issue #4

An empty visualized path in the scene tree that does not have spots defined until later (such as upon user action), can now have the warning suppressed by setting the suppress_warning attribute.

Version and example fixes

Minor update to include source files for examples and fix version number

Documentation updates

Minor documentation updates to this asset

1.0

The initial release of the asset