rebase again #3

Icon difference rendering

Please file any issues here.

Icons with diff:

ADDED - tests/dm/rsc/iconforge_gags_dm.dmi (0)

State Name (duplicate)	Old Icon	New Icon	Status
color_matrix (0)			Created
reference (0)			Created

ADDED - tests/dm/rsc/iconforge_tests.dmi (0)

State Name (duplicate)	Old Icon	New Icon	Status
dirs_1_frames_1 (0)			Created
dirs_4_frames_1 (0)			Created
dirs_8_frames_1 (0)			Created
dirs_1_frames_2 (0)			Created
dirs_4_frames_2 (0)			Created
dirs_8_frames_2 (0)			Created
dirs_1_frames_3 (0)			Created
dirs_4_frames_3 (0)			Created
dirs_8_frames_3 (0)			Created
noise (0)			Created
noise2 (0)			Created
noise_alpha (0)			Created
rgba_test (0)			Created