Create categories option after the scan profile is loaded

https://bugzilla.redhat.com/show_bug.cgi?id=1114063
Refactor call_scan and add tests

https://bugzilla.redhat.com/show_bug.cgi?id=1114063
Refactor coding style

https://bugzilla.redhat.com/show_bug.cgi?id=1114063
Merge pull request #111 from bzwei/customer_profile

Add profiles to categories option when a customer profile is included
Reset @display when viewing drift history screen.

Added change to reset @display when viewwing drift history screen to fix an issue where @display was still being set to vms/storages etc after clicking on links to relationships from host summary screen and then clicking on Drift History link from listnav on left side it was trying to render incorrect partial due to @display being set incorrectly. Drift History link from right side of the summary screen was working fine because going to summary screen resets @display back to "main"

https://bugzilla.redhat.com/show_bug.cgi?id=1123144
https://bugzilla.redhat.com/show_bug.cgi?id=1126085