Allow dots in field labels
Closes #746 (closed)
In !783 (merged) we disallowed dots in field labels as this caused exceptions when indexing these in elasticsearch (see #746 (closed)).
As we no no longer index every data field on it's own (as we hit max. field limits in elasticsearch) but instead as one big document a dot in a field name no longer is a problem (index wise).
We therefor want to allow dots again.