Address clang warnings - hud/hud.cpp:1310:3: warning: delete called on 'HudGauge' that has virtual functions but non-virtual destructor [-Wdelete-non-virtual-dtor]

git-svn-id: svn://svn.icculus.org/fs2open/trunk/fs2_open@10885 387891d4-d844-0410-90c0-e4c51a9137d3
From MageKing17: Patch for Mantis 3074: Correct mismatch between mission write and mission parse

git-svn-id: svn://svn.icculus.org/fs2open/trunk/fs2_open@10886 387891d4-d844-0410-90c0-e4c51a9137d3
Fix for Mantis 2960: Actually make sure that we're not performing invalid operations on a vector.


git-svn-id: svn://svn.icculus.org/fs2open/trunk/fs2_open@10887 387891d4-d844-0410-90c0-e4c51a9137d3