Comment 23 for bug 1599453

Committed revision 1642.

Add theme specific css file loading (from terminatorlib/themes and ~/.local/share/themes), move Adwaita fix into own file.

Should specify that only one file gets loaded, with the .local file taking precedence.

I've used the folder structure commonly used under /usr/share/themes. This is in case we decide to move things under there. I haven't made my mind up yet, but this implementation will do for now.

Word of warning. If you are switching themes, and using custom css, then we currently don't react to the theme change warning. This can result in a Frankenstein mix. Just open and close the prefs to force a reconfigure, and the correct custom css will be loaded.