add basic scaffold of scenarios, including the ability to add agents to scenarios, edit scenarios, and view scenarios.  next step: import and export
Merge remote-tracking branch 'origin/master' into scenarios
Merge branch 'master' into scenarios

Conflicts:
	app/assets/stylesheets/application.css.scss.erb
	app/views/agents/index.html.erb
	app/views/agents/show.html.erb
Scope menu
Merge branch 'master' into scenarios
better handling of return paths, and more specs
Merge branch 'master' into scenarios
allow exporting of a set of Agents with their links from a Scenario; Scenario guid is now generated and copied to export, as well as a source link when public
easier removal of agents from scenarios via the menu
Merge remote-tracking branch 'origin/master' into scenarios
diagram links back, export URL includes .json
upload and fetch by url, data object manages import; next step is actual import
Importing of Scenarios now works, creating any needed Agents by global guid
Merge remote-tracking branch 'origin/master' into scenarios
show description; allow updating of existing scenarios by URL
the import process now allows you to merge your agents with the incoming ones; next step is better UI
integrate dsander's suggestions
Merge remote-tracking branch 'origin/master' into scenarios
fix OpenStruct for 1.9.3
Add omniauth to let huginn consume oauth endpoints

Created a service model which stores external account information.
Created a service controller which kicks off the oauth process and lets
the user manage their external accounts.
Oauthable concern connects a agent to a service and adds a drop down to the
agents edit page.
Added a migration which converts the existing twitter agents to use the
new service model.