Allow list of commands to be injected into adam-cli AdamMain

[heuermh]

The list of commands in AdamMain is private, so outside of the PluginExecutor mechanism, adding new commands requires modifying this list and rebuilding; this also introduces a circular dependency between the adam build and an external project.

Adding a new constructor to AdamMain with a reference to the list of commands as a parameter would allow the list to be provided by dependency injection (e.g. via Guice).

https://code.google.com/p/google-guice/

[karenfeng]

Hey @heuermh, I was thinking about working on this issue. Are you already working on it, or can I go ahead?

[heuermh]

@karenfeng I don't have time to work on it now, so if you want to pick it up, please do so. I'll try to help where I can.

[heuermh]

Fixed by #762 and #854