Mark reactor default countdown times as const
Mark bitblt.c functions static
Adjust handling of weapon cycle with superlaser
Fix recvfrom prototype mismatches

Win32 uses int* instead of unsigned int*.  Fortunately, socklen_t is
defined to the correct type in both cases, so use socklen_t and let the
compiler sort it out.
Fix font prototype mismatch in SDL-only case

Commit 33bf139002533b2115251e9f391988001dc8fdc3 changed OGL
gr_internal_color_string to take a const char, but left SDL
gr_internal_color_string with non-const char.