Fix a warning with Linux/GTK2. DONT_BUILD.

git-svn-id: http://svn.eduke32.com/eduke32@4803 1a8010ca-5511-0410-912e-c29ae57300e0
Linux: Add detection of the Steam releases of Duke 3D and NAM. DONT_BUILD.

git-svn-id: http://svn.eduke32.com/eduke32@4804 1a8010ca-5511-0410-912e-c29ae57300e0
BSD: Fix the previous commit. DONT_BUILD.

git-svn-id: http://svn.eduke32.com/eduke32@4805 1a8010ca-5511-0410-912e-c29ae57300e0
Fix building the Build Tools. DONT_BUILD.

git-svn-id: http://svn.eduke32.com/eduke32@4806 1a8010ca-5511-0410-912e-c29ae57300e0
Fix building with `make -B`. (`make veryclean` is now obsolete.) DONT_BUILD.

git-svn-id: http://svn.eduke32.com/eduke32@4807 1a8010ca-5511-0410-912e-c29ae57300e0
Wii: Fix build. DONT_BUILD.

git-svn-id: http://svn.eduke32.com/eduke32@4808 1a8010ca-5511-0410-912e-c29ae57300e0