Pipeline-style promotion from one environment to the next

[kingdonb]

#62 describes the idea of multiple environments that are associated with a single app (repo), ref: #41

We need a way to arrange for the promotion of "lower" branches to build a pipeline

I believe this will require some completely new configuration language spec to describe the pipelines and their transition functions

I would not cry if it was possible for users to write the transition functions in Ruby

[kingdonb]

The basic idea is you need to write a function that returns "true" if the build passed, and that environment should be promoted from one lower environment to a next or further environment.

The function can perform some build or test step, or it can exec true after upstream work is done

[intellix]

This would allow it: #47