From Axem: adds getFrametimeOverall() lua function for timing purposes outside of gameplay

git-svn-id: svn://svn.icculus.org/fs2open/trunk@10967 387891d4-d844-0410-90c0-e4c51a9137d3
translation patch by Betrayal

git-svn-id: svn://svn.icculus.org/fs2open/trunk@10968 387891d4-d844-0410-90c0-e4c51a9137d3
From FUBAR-BDHR, chief1983, m!m and MageKing17: Fix for Mantis 2887: Additional workaround for mantis 2693

git-svn-id: svn://svn.icculus.org/fs2open/trunk@10969 387891d4-d844-0410-90c0-e4c51a9137d3