Added tests for clang condense plugin

no, but it does act  as a proxy that virtual calls are working correct (the number of calls specified in the csv is 3, but the call graph has 6 because inheritance).

Testing the whole thing would be abit tedious to write down since there's alot of metadata on the edges (the hash involves the qualified name, position, and a few other things).

I could check that 1 or 2 of the edges are in the set I suppose