adding iam role association to launch configurations
initial working version, tested on ubuntu.
Update main.yml

fix typo.
Adding matching tags for key length fix.
Merge pull request #220 from edx/e0d/tag-fix

Adding matching tags for key length fix.
Merge pull request #82 from edx/feature/e0d/iam-association

adding iam role association to launch configurations
Merge pull request #218 from hikari-boulders/patch-1

Update main.yml to fix a typo.
Add the abilty to provide a config file for the proxy command.
docopt not honoring default value.
Be able to turn off strict host checking.
Remove continuous-integration.yml which no longer exists.
Be able to place a read-only ssh credential for the jenkins instance.

Also add two more useful plugins.
Update the ruby role for issues found while testing jenkins role.

In certain states, ruby is installed but the env is not setup so it is importart
to always run the environment update task and the rehash task.

The rbenv install task prompts if the version of ruby is already installed. This
freezes the build so skip it if the version directory already exists.
Correct NAT Backup Image type.
Merge pull request #227 from edx/feanil/provision-vpc

Feanil/provision vpc
Be able to generate ssh config rules given a cloudformation stack name.
Merge pull request #228 from edx/feanil/vpc-tools

Be able to generate ssh config rules given a cloudformation stack name.
Add more control over rabbit and worker instance types.
Merge pull request #229 from edx/feanil/cloudformation_customization

Add more control over rabbit and worker instance types.
remove mongo server from requirements