Document errors

[3rd-Eden]

We don't have any documentation on how to handle the issues that are sometimes returned during deployments. For example;

Cannot start application with no snapshots

We should tell them that they have only created the application but have no uploaded their application to our servers yet (assuming that people don't know wtf a snapshot is)

There are a buch more of these errors in our nodejitsu api.

[mmalecki]

We should probably return understandable errors instead.
I find WhiteHouse/api-standards to be an interesting standard for errors.

[julianduque]

+1