[PR] General improvements to provisioning and documentation

* [x] Add create privileges to MySQL users. This also affects production, though it may be interesting to see if we can remove create privileges for production users at some point. This would prevent things like installing plugins that add custom tables until they've been fully vetted.
* [x] Add documentation around pillars.
* [x] Remove old pillar data directory
* [x] Unify WSUWP vagrant and production minions into one configuration
* [x] Refresh general README