Slow dependency sorting

[ivanka2012]

https://github.com/horsicq/PDBRipper/blob/ea59ac53834fb1b6572b510acc09ccdcf81f920d/qwinpdb.cpp#L2954-L2987

Currently, sorting by dependency during a C++ header export is done by a bubble sort, which you can see linked above. WIth a decently sized PDB, this procedure is really, really slow.