Fixes #12852 - override checkbox always enables default value when use_puppet_default is false

Fixes #12842 - Adding padding below use puppet default checkbox in puppetclass edit form

Refs #6007 - fixing safe_value for lookup key

Fixes #12828 - Hidden value checkbox enabled after override button is checked

Fixes #12827 - deconstantize resource only when needed

Fixes #12806 - adding merge_default to attr_accessible in lookup_key

Fixes #12799 - Add uuid to Compute Resource attr_accessible

Fixes #12180 - lookup_value presence validation moved from lookup_key

Global parameters can have empty values so smart variables that are also global should be allowed to accept empty values too.
The validation on lookup_value to make sure it isn't empty is in the LookupKey class therefore affecting both VariableLookupKey and PuppetClassLookupKey....

fixes #11862 - validating that casted hash is valid

Catch parse errors correctly under Ruby 1.9.3, and ensure the uncasted
value is displayed back in the UI if it fails to parse.

Fixes #12278 - make sure permission set is uniq for role

If default user has two or more filters with same permission (valid
setup), the verification of found collection failed. This patch
make the list uniq and the check correctly verifies whether all
permissions were found.