Getting FPS and UPS directly from the StatManager

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The functions GetFrames() and GetUpdates() only return the current frame- or 
updatecount since it's last reset as a second was over.
Whith that information the user would then have to create again his own clocks 
and synchronize them somehow with the StatManager clocks to be able to 
calculate the FramePerSecond or UpdatesPerSecond rates.
But on the other hand StatManager does calculate the FPS and UPS every second, 
so it actually could return those rates, even if they are not from the current 
second, but from the last one.

With that said, it would be nice to have two functions in the StatManager, 
which returns
a) the FPS
b) the UPS

The UPS is essential for calculating the next move of any moving object, 
otherwise it would end up being dependend on the process power.

Original issue reported on code.google.com by youtube@my-gate.net on 14 Feb 2011 at 12:36