Fixed bug where a script class could be incorrectly marked as non-garbage collected when including a garbage collected member by value

git-svn-id: https://angelscript.svn.sourceforge.net/svnroot/angelscript/trunk@1542 404ce1b2-830e-0410-a2e2-b09542c77caf
Added the global functions asAtomicInc and asAtomicDec to aid the development of portable and threadsafe add-ons

git-svn-id: https://angelscript.svn.sourceforge.net/svnroot/angelscript/trunk@1543 404ce1b2-830e-0410-a2e2-b09542c77caf