Add extra datatype integrity test

For https://tickets.puppetlabs.com/browse/RAZOR-135
Add "lower" & "upper" matcher functions

To facilitate case-insensitive string matching for instances like MAC addresses, functions "lower" and "upper" have been added to the matching language. This will allow, e.g. `["=", ["upper", ["fact", "macaddress"]], "F0:1F:AF:D8:F2:A6"]`

Fixes https://tickets.puppetlabs.com/browse/RAZOR-89
Link repo to task

The association between a repo and a task should not be indirect through the policy. Repo requires an association to task. Policy has an optional association to task, which will help with backward-compatibility.

Fixes https://tickets.puppetlabs.com/browse/RAZOR-143