Commenced teaching the ansible deployer plugin some new tricks.
Step one: assert some things about the options we're given.
Step two: make the help string describe the intended new feature.
Gave the deployer a completely new command parser.

This one returns a hash with fields for each of the pieces of
the command.

action: help or deploy
script: name of ansible script
environment: inventory file to use
branch: branch or hash to pull from

Wrote tests for the parser.
Wired up the new deployer command options to the function
that calls ansible.

Expanded the help text to include available scripts & inventories.
Test coverage is lower than I'd like because none of the tests invoke
ansible. Also the ansible output rollup isn't great. Both features
for another day...
Updated the readme.
1.1.0
Merge pull request #12 from ceejbot/ceej/deploy-tricks

Taught the deployer plugin some new tricks