for relative skin paths used in the ufo:ai md2 models (these take the form of ./blah.tga
and such, and refer to files in the same directory as the model)
git-svn-id: svn://svn.icculus.org/gtkradiant/GtkRadiant/trunk@122 8a3a26a2-13c4-0310-b231-cf6edde360e5