New python API for units handling.

Exposes all supported unit systems & types, and to_value()/to_string() functions.

Reviewed and enhanced by CampbellBarton, many thanks!

Differential Revision: https://developer.blender.org/D416

release/scripts/modules/bpy/utils.py

@@ -44,6 +44,7 @@ __all__ = (
     "script_paths",
     "smpte_from_frame",
     "smpte_from_seconds",
+    "units",
     "unregister_class",
     "unregister_module",
     "user_resource",
@@ -58,6 +59,7 @@ from _bpy import (
     )
 from _bpy import script_paths as _bpy_script_paths
 from _bpy import user_resource as _user_resource
+from _bpy import _utils_units as units
 
 import bpy as _bpy
 import os as _os