Add ability to specify custom python requirements.

This lets you specify additional python packages to be installed
into the edxapp virtual environment.

The `EDXAPP_EXTRA_REQUIREMENTS` should be a list of dict objects
with `name`, `version` (optional) and `extra_args` (optional) keys,
that correspond to the options of ansible's pip module.

Example:

    EDXAPP_EXTRA_REQUIREMENTS:
      - name: mypackage
        version: 1.0.1
      - name: git+https://git.myproject.org/MyProject#egg=MyProject
Merge pull request #1690 from edx/will/gather-facts-for-security-role

Gather facts so the security role succeeds - into release
Merge pull request #1035 from mtyaka/extra-requirements

Add ability to specify custom python requirements.
harprofiler ami creation via packer.

TE-583
Merge pull request #1687 from edx/benp/packerify-harprofiler

harprofiler ami creation via packer.
Work around for an issue in the Route53 module.

See: https://github.com/ansible/ansible-modules-core/pull/310
Merge pull request #1698 from edx/feanil/lowercase_dns_rel

Work around for an issue in the Route53 module.
Merge pull request #1691 from edx/release

Merge release into master
Compiling Insights Translations

The virtualenv must be active in order for i18n_tool to run properly.
Merge pull request #1700 from edx/insights-translations

Compiling Insights Translations
backporting latest module
Merge pull request #1704 from edx/e0d/pullin-mongo-user

backporting latest module
Added Support for Django 1.7 for Analytics API and Insights
Put all keys in the authorized_keys file.
Merge pull request #1702 from edx/analytics-django-1.7

Added Support for Django 1.7 for Analytics API and Insights
Refactoring to repair user creation

bootstrap admin creation

removing debug flag

new local module

rename

Changing to string from list

porting Carson's upgrade

removing create user flag

refactoring handling of 2.4

removing to another pr

making autograde gated by cluster status

pulling in Carsons changes

Carsons changes to cluster

rename

Carsons changes

Adding template for root user

Updating vars

Removing colon

whitespace

whitespace

module name

restore missing code, whitespace, update vars.
* playbooks/roles/mongo/templates/repset_init.js.j2:

restore whitespace

typo

adding replica set, needs testing on sandbox

updating vars

One more var

sigh

Removing auth, unsure this is needed
Adding auth back
Merge pull request #1696 from edx/e0d/mongo-roles

Add roles
New AMI
Merge pull request #1706 from edx/e0d/update-ami

New AMI