Bug 1582039: Show submissions by default for 'allow submissions' groups

This patch does 2 things:
1) Changes all groupviews blocks on groups that allow group
submissions but don't have showsubmitted set to set it as true
2) When creating a new group that allows submissions to set the
showsubmitted = true at that time.

Change-Id: I8dbc7f9f4919fbb21aded3ff0f2637152b4d3480
Signed-off-by: Robert Lyon <robertl@catalyst.net.nz>