Remove data related to cobbler classes

A few relics of data for direct access to the cobbler:: classes
are still hanging around.  They're not necessary any longer since
we now drive cobbler via coi::profile::cobbler_server.  This commit
removes the traces of the old data to avoid confusion.

Closes-Bug: #1269126
Merge pull request #34 from CiscoSystems/bugs/1269126

Remove data related to cobbler classes