This patch does a few related things:
#removes a lot of unused and weird stuff from problemreporter
#all parser activation decisions are moved back into cppsupport where it belongs, problemreporter is just UI
#fixes flickering problem tabs
#fixes a case where already open documents don't get a problem icon marker
#fixes sorting so it happens numerically, no lexographically
#afaik fixes repeated entries. if this still happens, I don't think problem reporter is responsible
#afaik fixes the remaining cases where the parser could be invoked against non-c/c++ files