Db_Row_Aggregator: renamed collectGroup() to groupMany(); tweaked tests
pulled Relation.php from a certain commit;
for some reason it was not included in the previous merge.
added array check in Map#get. i already fixed this before. dafuq
Map: chaned \!is_array to is_string to resolve conflict in the master branch
Merge branch 'feature/entity'
replaced 'static::' with 'self::' for 5.2 compatibility