Added event after the ssh pool is setup

[delmendo]

The current emit(init) happens too early. In order to improve configuration options for the shipit-bastion I need a hook after the pool is setup so I can modify it with the options for the proxy I'm inserting. This should not impact any current users but should make shipit more flexible.

[gregberge]

Hello @delmendo, are you sure that you can't plug you anywhere else? If not, we still have to document it. Can you add a line about it in the readme? Thanks!

[delmendo]

I looked at taking over the initialization of the ssh pool itself but the code that exists doesn't check to see if the pool has already been setup. This seemed the lightest way possible to get the stage I needed (The pool has been setup by the main system and won't be overridden by the main package). I tried to make it so that it would do the least possible change to the core project.

I added in documentation for the emit events and a note about the other events that are hooked into by the cli through orchestrator (Since I didn't seem them covered anywhere else). Please let me know if I need to do anything else.

[gregberge]

OK thanks, @delmendo tests are broken, can you try to fix them?

[delmendo]

I added tests for the emit methods (the one I added and the one that was already there). Looks like the build is now clean :)

[gregberge]

Thanks!