Fixes #7624: validation for location and organization long names instead of an error

@orrabin, The matcher possibilities are only `hostgroup=`, `location=`, and `organization=` for the classes that `include NestedAncestryCommon`. ``organization=` is 13 characters, so I would take some more buffer room and do this
```ruby
validates :title, :length => {:maximum => 240} # max is less than 255 characters since to allow space for lookup value matchers
```
To me in makes the code more readable that trying to optimize the max length for hostgroups is 245 chars, for location 246 chars, and organzation 242 chars.