Fix for existence of Storage Manager Type value during validation

A blank value for StorageManager Type was not being checked while
validating the credentials.

https://bugzilla.redhat.com/show_bug.cgi?id=1123962
Fixed typo in admin role features list

https://bugzilla.redhat.com/show_bug.cgi?id=1129284
Merge pull request #376 from dclarizio/add_route_for_sorting_pxe_grid

Add route for pxe grid sorting
Merge pull request #371 from AparnaKarve/bz1123962_storage_mgr_validate_creds_issue

Fix for existence of Storage Manager Type value during validation