Add script to update 1k+ group wmf_donor stats

Fixes stats for WMF LYBUNT if merges or other db manipulation has
gotten them out of date.  Runs with minimal table lockage (.25 sec
max update time to wmf_donor in dev_civicrm).

Change-Id: Ifaccdf618f47240b30f22feeb6ae33696d415657
Update wmf_donor fields after merge

Would be nice to hide them in the list of mergable things, but
Rosie says they're not too much of a pain there.

Change-Id: Ic7288f29bd061bf17274ab4fb4bc8d2105340b21
Fix WMF post-merge recalc breaking when no donations

Without the 'group by', this was trying to insert nulls

Change-Id: I3b1b0d8d8fb025120622298389d26c8dc4ee4769
Merge branch 'master' into deployment

b0d1ba0 Fix WMF post-merge recalc breaking when no donations
33ba5de Update wmf_donor fields after merge
bbf1f17 Add script to update 1k+ group wmf_donor stats

Change-Id: If5f2806f2ba559ce3eb1bba731da802856a1857f