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

* I've moved the example secure directory to playbooks/secure_example,
  the directory structure in your secure repo should mirror that in
  secure_example/
* If you run the lms role without a valid git-identity file it will
  fail, there is an empty file checked into the secure_example dir
* Using GIT_SSH env for git checkout, we will also need to use that
  for pip installs that use git if there are private repos in
  requirements.

This keeps vars that are specific to roles with the role, not
very well documented except in the playbook example here:
https://github.com/ansible/ansible/blob/devel/examples/playbooks/roletest.yml

This makes playbooks more concise since you do not have to explicitely
include vars for each roles, var_files will still override any of the
default values in <role>/vars/main.yml

* Pre-commit hook lints JSON
* Post-checkout hook causes hooks directory to update with current
  project hooks
* Readme updated so installation section reminds you to install hooks

* It can be either way (ansible doesn't care) but it should be only one
  way, and the preponderance of existing configuration used .yml.
* Update to README to reflect changed filenames.

* Make it convenient (albeit, mandatory) to set AWS region on the
  command line when calling ansible-playbook for cloudformation

* Wrap to 80 columns
* improved markdown conformance and plaintext readability
* note about setting PYTHONPATH inside squeaky clean virtualenvs
* note about using WikiWords as your cloudformation stack names
* note about how sometimes ansible says 'ok' when cloudformation says
  something broke

changed ansible version to 1.1 in requirements.txt
updated the ec2 tag in test.yaml