Squashed 'machine/' changes from 8a9ed97..a0d8669

a0d8669 using environment variables for config
2a970fe fix readme styling
05d97a3 parameterize machine config

git-subtree-dir: machine
git-subtree-split: a0d8669a46e454ee6644f127a6de4b1f4029f5bf
Merge commit 'aa65812ef9416b551cb1045037a0c65df0197cf4'

Conflicts:
	machine/Vagrantfile
	machine/provision.sites.sh
	machine/readme.md