Vsync: Put it back to half slices, there seems to be games which don't like the vsync timing more accurate either way. Until i can work out why we will go back to the old half n half timing which all known games seem happy with.

git-svn-id: http://pcsx2.googlecode.com/svn/trunk@5903 96395faa-99c1-11dd-bbfe-3dabce05a288
If you're gonna do a revert, you might as well do it properly :P If you don't want it doing properly, give it to me.

git-svn-id: http://pcsx2.googlecode.com/svn/trunk@5904 96395faa-99c1-11dd-bbfe-3dabce05a288