GitLab

When the `branch` parameter is passed to the versions_controller,
a 404 is returned because g5k-api doesn't find the specified branch.
This is because of a missing concatenation with `origin/`, indeed
g5k-api's reference-repository only holds remote git references.

The role of this method was to list users for a vlan, this is covered in
VlanUsersController.

Before, the returned JSON contained only "ok" when a node was added to
vlan or "unknown_node", and nothing if the node was already present in
vlan.
Now, it will add a status and message field, for each case (successfully
added, unknown and already present in vlan).

This allow to have the same hash as the one returned on
`/vlans/nodes/{node}` resource

Add a glue to wrap kavlan's API

See merge request !80

In Kavlan, global vlans from other sites are called 'kavlan-remote'. To
be more understandable we choose to rename it.

This allow to list vlans, fetch a specific one and manage the dhcp
server for a vlan

Rails already had the parsed payload to params

Add resources param on job controller index

See merge request !81

This GET param allow to query the job list with the two additional
fields `resources_by_type` and `assigned_nodes`.

If the disk resource type doesn't exist in OAR's database, we add it to
the possible types so we can have it (empty) im the returned JSON.
Some applications need the disks key, even empty.

Add storage endpoint

See merge request !79

Expose all OAR resources on status api

See merge request !76

This route causes the node controller to fail with "No route matches"
error when requesting nodes for a cluster.

Refresh fake reference-repository

See merge request !78

Return 404 when a commit or a branch cannot be found

See merge request !77

Add the ability to return a deep view of reference-repository

See merge request !74