A single-node master/minion Salt setup

* Bumped salt-bootstrap to 1.5.6
* Now relying on Git-latest salty-vagrant
* Generating PKI infrastructure using a Makefile
* Using those keys to seed the master and the minion
* Using a separate shell provisioning step to wait for the minion to connect before running off
* Using special hostmanager function trick
Merge branch 'release/1.2'