Make AdaptationManager::loadBalance always load balance the grid
Currently, AdaptationManager::loadBalance will only load balance the grid every balanceStep calls (by default, no load balancing takes place at all). This is quite confusing to the user. Moreover, loadBalance will not communicate the discrete functions; this is only done in adapt.
With these patches applied, loadBalance will load balance the grid on every call and communicate the discrete functions after load balancing (for consistency). The behavior of the method adapt is unchanged, i.e., load balancing will only take place every balanceStep calls to adapt.