[1.8.0] Small matcap bug

[wojtek]

If you try to load a file with the same name (or full path, i didnt check) it won't actually replace the current loaded matcap file even if the file itself has changed.

[Alexey Pasumansky]

Hello wojtek,

Seems that it have to be the same absolute path to matcap file, and only in this case the modification of the file contents doesn't apply. We'll check if it could be fixed quickly.