Added /vlans/:hostname route to the API
Added a total vlan response in api
Updated vlans returned, was a double array by accident
missed out the response code and header
Updated route url to /api/v0/devices/hostname/vlans
Moved vlans route + updated docs
Merge pull request #300 from laf/issue-laf-44

Added a route to the API that will get vlans for a given device