fixes #345 - unable to save associated operatingsystems

fixes #344 medias pages do not show error messages

requireing the sha1 library, refs #145

Fixes #145 - Added AuthSourceInternal

Added a password setting facility to the user class for AuthSourceInternal
Switched to SHA1
Changed :ldap to :login
Applied numerous fixes from Ohad Levy
Fixed malformed user page
Switched attr_accessible to attr_protected...

fixes #331 - Operating system edit page error messages are out of alignments

Fixes #260 - Switch to using STI for OS families

fixes #321 - external-node importer does not overwrite class list

fixes #326 - Host resource graph legend is mislabelled

fixes #238 - Set Content-Type HTTP header when rendering nattended install scripts

Fixes #261 - parameters now use a single reference_id

This implementation uses STI but the table looks the same for all
variants. This is a little strange but it seems to work.

Also removed obsolete controllers and tests
Added more tests