#223 Build failure: wrong linker

[Darren Salt]

After reworking my build system somewhat (now using internal deh_edge & epi since edge is the only user, and external glbsp since edge isn't the only user - this requires one #include change), I noticed an odd build failure: various symbols weren't being found by the linker.

A little investigation showed that gcc was being used at link time instead of g++, which will automatically pull in the necessary C++ libs - these are enough to fix the problem and allow a successful build (with patches for bugs 1414752 and 1622082 and to disable hawknl usage).

The attached patch fixes the problem.

[Darren Salt]

Fix the linkage failure