Add cursor theme

Originally from Jakub Steiner's dmz-aa theme
Fix Makefile syntax
Adwaita cursors

- import all the sources
- don't composite blender spinner, use a simple one (8 frames) directly in the SVG
Add some depth to the wait cursors. They were too flat.
Updating kn translations
Update git.mk
build: update .gitignore

Don't use git.mk, just a static .gitignore.
themes: Fix enumeration of cursors with srcdir != builddir
Rename directories for merge
Merge cursors

from gnome-themes-standard