Fixed up IGameHelpers.h such that it no longer requires HL2SDK headers if a function doesn't need them
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extra : convert_revision : svn%3A39bc706e-5318-0410-9160-8a85361fbb7c/trunk%402144
Fully implemented amb734 - Including console interface and menu for clients to use.
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extra : convert_revision : svn%3A39bc706e-5318-0410-9160-8a85361fbb7c/trunk%402140