Add EventDrop#created_at and drop (skip_)created_at from EventFormattingAgent.
Allow HipchatAgent to use a shared credential
Add Bountysource link/badge to README
Break Diagram into it's own controller, nest resources

Conflicts:
	app/views/scenarios/show.html.erb
Merge pull request #417 from knu/add_created_at_to_event_drop

Add EventDrop#created_at and drop (skip_)created_at from EventFormattingAgent.
remove created_at from default options
Merge pull request #419 from drcapulet/hipchat-shared

Allow HipchatAgent to use a shared credential
Merge pull request #422 from drcapulet/route-changes

Break Diagram into it's own controller, nest resources
Stop adding "(Disabled)" to disabled agents.

They are now distinguished by the color and line style.
Set the digraph title to "Agent Event Flow".
Show the agent type in tooltip.
Put a badge indicating the number of events created on each agent node.

It is clickable, and colored depending on its status.
Add a tooltip to badges.
Turn the JavaScript code into a separate CoffeeScript file.