Changed TextureBrowser filter to case-insensitive.
Extended NonModalEntry to support "changed" callback and to make focus manipulation optional.
TextureBrowser filter entry now won't loose focus after seraching.
Added _filterIgnoresTexturePath and _filterIsIncremental flags for filter in TextureBrowser.
Both default to false.
Turned on _filterIgnoresTexturePath and _filterIsIncremental.
Changed all occurences of "textures/" to GlobalTexturePrefix_get().
Fixed compilation error in MathTest::testTransformation().