updates
smokefps
big changes in timing:
	- the time atom is kept to 1 ms, but the engine should be now independent (barring floating point inaccuracies) on fps and on the exact order of calls to updates
	- curtime and elapsedtime make no sense anymore. A macro is provided to emulate them locally, and they provide a variable that works as the old curtime/elapsedtime but is guaranteed to work properly in sub-millis engine refreshes
	- game::updateworld() silently refused to do its job if called more often than 1 ms apart. This means that multipoll newer worked, and actually increased input lag because the engine was refreshed only when there was a big frame drawing delay (what's placebo effect again?)
	- mouseaccel works now on elapsedtime
smal readme update