cloudformation: open tcp/9418 for git

Jarv/better elb rolling

This rolls the ec2 elb management script into a module.
Now if an ELB is added or removed "changed" will return True/False
so you can tell if any action was taken based on the coloring of
the response (yellow/green).

role for upstart tasks, parameterized in the style the nginx role

Happened to notice this while I was in here, mostly a cosmetic fix.

Tiny documentation update

Update 'edx' group to 'adm' group in LMS setup

* Use the 'adm' group for permissioning assets needed during LMS
  initialization, because ubuntu doesn't have the edx user until it logs
  out and logs back in.

where it can take a {{ service_variant }} param

We need to use the git protocol to access read-only git repos.  It's a
quirk that when these are referenced from pip files, they need to go
over a source control protocol.  I wish it could go over http/s or ssh,
but it can't, so port 9418 it is.

I had to open inbound and outbound 9418 to get this working, don't know
why.  Leaving both open for now, will debug later so we can close down.

Add site-specific parameterization for nginx config

Update permissions on git identity files

* Add ubuntu to edx, restrict git identity access to edx group members

Updating mitx repo location

mitx is now in the edx org

bugfix install of example user (needed secure_dir)

Coudformation refarch template: fix elasticache creation output

cloudformation template changes for outbound SSH, internal DNS names

npm install  playbook

change directory structure ascii art to reflect current status (secure_example)

Refactor how we manage secure data, git-identity changes