cyclades: Fix bugs relative with quotas
* Reject previous unaccepted serials if action is 'DESTROY'. This is required because multiple DESTROY actions may be pending for the same resource (e.g. VM). The one who succeeds will be accepted, while all others will be rejected. This isn't optimal since it causes circular issuing and rejection of commissions and should be fixed in a better way. * Update dispatcher to handle commissions before updating the state of the VM, since if a new commission will be issued, this commission will depend on the state of the VM.