Merge pull request #474 from nextcloud/group_shares

apps/files_sharing/lib/MountProvider.php

apps/files_sharing/lib/SharedMount.php

apps/files_sharing/lib/sharedstorage.php

apps/files_sharing/tests/MountProviderTest.php

build/integration/features/bootstrap/Sharing.php

build/integration/features/bootstrap/WebDav.php

build/integration/features/sharing-v1.feature

core/js/shareitemmodel.js

core/js/tests/specs/shareitemmodelSpec.js

lib/private/Repair.php

lib/private/Repair/RepairUnmergedShares.php

tests/lib/Repair/RepairUnmergedSharesTest.php

version.php