fixed bug with start/stop buttons
Fixed BUGgit add -u invokeMethod was outside of if statements and therefore simulateTimeStep was getting called twice simulatenously by two threads
working on the time stuff
update to time stuff
computing sim time, real time, relative time (instantaneous and overall)
Merge remote-tracking branch 'origin/feature/simulation' into slohia

Conflicts:
	src/gripmainwindow.cpp