`php5-json` isn't a required package for 13.04, so don't try to install it.

Trying to install it means it fails, and then fails to restart PHP-FPM. We'll need to make sure it's installed when we upgrade to 13.10
NPM is dependent on `nodejs` and `python-software-development`
Some non-functional code that attepts to get MySQL to mount its directory with the proper permissions
Remove backwards compat for less than Vagrant 1.3
Take the easy way out and drop explicit support for databases in a mapped directory

Instead, developers can opt-in to this approach using their `Customfile` and copying their database files over.
These files don't really need to exist for Vagrant
NPM comes with Node
Merge pull request #76 from humanmade/fix-initial-provision-76

Fix full provision of Salty WordPress