Blender Git Loki

GPencil Stroke Editing: Stroke Editmode now behaves like other editing modes for objects

You can now enter stroke editmode from the usual mode dropdown in the 3D View
header. While this isn't strictly correct (data-wise, GPencil datablocks can
belong to stuff other than the active object), for the most common use case
of usage in the 3D view, this is appropriate.

Notes:
* This still needs more careful checking to ensure correctness/consistency of
behaviour in all edge cases (e.g. gpencil datablock in a different editor,
or user manually changed the mode toggle, etc.)