Merge pull request #561 from Foggalong/master

Updates the hardcoded list to reflect #564, #566, #569 and #570 & removes a duplicate kindle icon.
Proper-ish gthumb icon.
Fixes #573.
Fixes #574. Fixes #575. Fixes #576. Fixes #577. Fixes #374. gnome colour manager fix.
Redid some icons.