Group shares support

[PVince81]

• find/enable matching API tests to see where it's missing

@individual-it I guess this is likely hidden by owncloud/ocis-reva#34 ?

[individual-it]

@PVince81 yes, to test/try sharing the test infrastructure needs to have some info about the groups

[stale]

This issue has been automatically marked as stale because it has not had recent activity. It will be closed in 10 days if no further activity occurs. Thank you for your contributions.

[individual-it]

the group endpoints exists, so need to find out why tests still fail

[stale]

This issue has been automatically marked as stale because it has not had recent activity. It will be closed in 10 days if no further activity occurs. Thank you for your contributions.

[C0rby]

Group shares are working.