Add set_env script

We made this script location agnostic and moved it to here from the
Puppet config.
Add initialize_node command

We moved this into here from our Puppet config.
Add Puppet independent initialize_node command

We also added a config directory to store variables like the Node
version.

We will now move all of this into a separate node-site template.
Move Node site commands into node-site template

We moved the command for the general node-site into the node-site
template. We may not update the create_express_site command to work with
node-express in this way, but cloning node-site is how we will start
development on any kind of Node site in the future. This includes
possible Meteor.js sites.
Add main site directories
Add starting site README

This starting README contains details about how to run and maintain the
site.
Add create_compound_site command
Add create_express_site command
Add details of node-site template
Add standard .gitignore