Addresses the remaining portions of T77137 (Python API for Controller
Interaction), which was partially completed by D10942.
Adds an XR "action maps" system for loading XR action data from a
Python script. Action maps are accessible via the Python API, and are used
to pass default actions to the VR session during the
xr_session_start_pre() callback.
Since action maps are stored only as runtime data, they will be
cleaned up with the rest of the VR runtime data on file read or exit.
Reviewed By: Julian Eisel, Hans Goudey
Differential Revision: https://developer.blender.org/D10943
e844e9e8f3