Do not allow loop_halve and loop_double to activate beatloops

Tested latest lp:mixxx/1.10 Mac OS X 10.6.8

I dunno if this behavior is intended but it feels surprising and out of place

1. Load and play a track
2. Hit the 4-bar loop button
3. Hit the reloop button to de-activate the loop
4. Hit the "loop_double" (+) or "loop_halve " (-) button
5. See that a new beatloop is activated , deleting the old inactive one

There is no problem with loop_halve , loop_double altering the length of an (de)- activated loop , but i think both controls should not be allowed to set a new loop.