make the tcl command "integrate" less dependent on autoupdates

if i saw it correctly the behaviour of the integrate function depended on the whether autoupdates of observebles or correlations where enabled or not.
e.g.
integrate 10000 recalc_forces
would have recalculated the forces every time step, if autoupdates are enabled, if not, only once at the beginning.
That is not really necessary, since recalc_forces will be 0 anyways.