Release 0.4.0

Change dryrun to test

Small tidy of code

Rework terraform class

Move deployment logic to case statement

Add further end-to-end tests

Reduce repeated code in CLI spec

Merge pull request #20 from surminus/refactor-config

Add end-to-end tests for CLI

Don't check for packages on dryrun

Skip all all of git check if specified

Tidy up config_file method

Refactor config into separate class

Release new version

Enhance data hierarchy