74d5a93b2b
Display the bone axes at the head (root) of the bone by default, instead of the tail (tip), and add a slider so that it's possible to adjust this position. Versioning code is in place to ensure existing files behave the same (axes shown at tail), whereas new Armatures will be using the new default (axes shown at head). Reviewed By: #animation_rigging, #user_interface, Severin, Sybren Differential Revision: https://developer.blender.org/D7685