Resolve a series of Xcode (LLVM compiler) warnings

git-svn-id: svn://svn.icculus.org/fs2open/trunk/fs2_open@9735 387891d4-d844-0410-90c0-e4c51a9137d3
Fixed bug in RotationalVelocityDesired documentation.

git-svn-id: svn://svn.icculus.org/fs2open/trunk/fs2_open@9737 387891d4-d844-0410-90c0-e4c51a9137d3
Fix MSVC warning (int to char conversion): thanks to zookeeper for noticing this

git-svn-id: svn://svn.icculus.org/fs2open/trunk/fs2_open@9739 387891d4-d844-0410-90c0-e4c51a9137d3
Fix for mantis 2904: redalert wingmen without RA data are treated as destroyed

git-svn-id: svn://svn.icculus.org/fs2open/trunk/fs2_open@9740 387891d4-d844-0410-90c0-e4c51a9137d3