Render group with folder view
api: Shorten name of authorized_keys index.

I had trouble running the new TimestampsNotNull migration, because I
ran into the index name limit described in the migration comments.
Running this migration first worked around the problem for me, and I
hope it saves others from tripping over it too.
api: Test VM login scopes.

The virtual machine controller is the only one doing anything
interesting with API token scopes right now.  I'm writing this test
for that functionality to make sure it stays effective through
refactoring.
api: Introduce path-based API token scopes.

Refs #1904, #2662 for background discussion.
api: Migrate VM auth scopes to new system.

VirtualMachinesController was the only one doing anything special with
API token scopes before we provided the more general-purpose system.
This commit removes its specialized code, and provides a database
migration to convert those specialized scopes to the general-purpose
schema.
api: Support scope searching in API token index.
api: Support filters in API client auths index.

Per comments on Refs #1904.  filters is generally the preferred way to
do searching now.  I maintained existing limits on what can be
searched with this method.
Show folder contents with editable names.
Add sb-admin layout.
Add folders page, backed by groups.
Merge branch '2640-folder-api' into 1970-folder-view
Merge branch '2640-folder-api' into 1970-folder-view
Rename owned_items to contents.
Make "create folder" button work
Move folders into a separate controller. Add description-editing.
Fix no-side-nav mode.
Fix "create folder"
Merge branch '2640-folder-api' into 1970-folder-view
Use separator instead of drop-down for less-used nav links.
Fix tests to work with new css/layout.