Improved Vagrant usage

Moved to using CentOS for the Vagrant box, like production
Moved to using Puppet for provisioning
Fixed docs
Increase REPL timeout b/c Vagrant is slow
Disable Vagrant machine firewall

This allows us to connect via nREPL and via Mongo.
Merge pull request #192 from cndreisbach/vagrant

Converted vagrant to work like CFPB production