rightscale.sever_array.Execute actor integration tests.
Properly handle missing RightScale Script response (None).
Handle two additional rightscale.server_array.Execute failure modes better.

1. If the RightScript doesn't exist, throw a reasonable exception.
2. If the Inputs are incorrectly formatted, throw a reasonable
exception.

For both cases, implement integration and unit tests.
Merge branch 'master' of github.com:Nextdoor/kingpin into execute_integration_tests
Typo fix
Merge pull request #19 from Nextdoor/execute_integration_tests

rightscale.sever_array.Execute actor integration tests.
Move dev-docs into their own file.
Merge pull request #20 from Nextdoor/breakup_documentation

Breakup documentation
Add AWS Actors using boto.
Add simplejson to requirements.
Add SQS "wait until empty" Actor
Add ELB-Wait Actor

* UNTESTED
Minor code refactoring

* Create AWS base class (not a base actor)
* Use tornado_sleep() everywhere
Add unit tests for aws.elb actor
Minor tidy up here and there
Major refactor of AWS ELB Actor.
Small improvements to AWS SQS Actor
AWS ELB Actor improvements and tests.
Specify boto version in requirements.txt
Patching ELBConnection to help TravisCI