Make printers do the same things as images, snapins, hosts, groups, etc...

git-svn-id: https://svn.code.sf.net/p/freeghost/code/trunk@2326 71f96598-fa45-0410-b640-bcd6f8691b32
Fix error throw on 393 of printer page.

git-svn-id: https://svn.code.sf.net/p/freeghost/code/trunk@2327 71f96598-fa45-0410-b640-bcd6f8691b32
Merge svn with master