Fixes #8414 - extracts validators from models

Also cleans up some unused validators looking for trailing whitespace
that is stripped by the StripWhitespaces concern.
Tried to make some sense from unmatching regexps and validation error
messages. Some validations might need a different regexp to check for what...

Fixes #7733 - Remove hosts.yml fixtures and use FactoryGirl instead

Fixes #5692 - correct counts in cached_counters

fixes #4256 - makes columns sortable in the UI

fixes #2378 - added Minitest and other code cleanups

fixes #1509 - Foreman should use the proxy to import puppet classes

Fixes #239 - Erases environments and puppetclasses

The fix also includes a page in which the use selects the additions
and removals which they would wish to apply to their database.
Errors are reported and an opportunity is given to reapply the changes.

Fixes #256 - Environment names should be alphanumeric

finished tests for environment

removed trailing spaces

Added environment test. It's green, but it lacks some tests.

realigned models to use :though and habtm when it made sense, setup basic AS controllers to support that