Fixes needed for new join functionality in modifier class

When joining to the list of tables in a query we need to change the
comma-separated table list to a cross-join list so that any table in
the list can be joined to.
Tweaking participant report
Making participant.other_name NULLable and NULL by default
Tweak to participant multi operations to show "no participants" message

By leaving the modifier empty the "no participants have been selected" message
will appear instead of the generic argument error when the UID list is left empty.
Adding COMMON_LAW (as well as COMMON-LAW) to opal manager label cache
Bumping to next version
Merge remote branch 'origin/release' into develop