[WIP] Angular Prototype for Repository Editor

- Added a controller specific to the repository editor form
- Added a directive specific to the repository editor form
- Added a couple generic directives that would have an application-wide usage
- Changes made to RepositoryController (@edit related changes)
- Added a JS function to display flash messages triggered through Angular events
- Added Jasmine tests (WIP - need to add a few more)

#1064
If this is the only place that ```setFormToValid``` is used, you could instead just define it as a function ```var setFormToValid = function()``` and on line 57 you would not call it on $scope. If you plan on using this function in the DOM somewhere though, then leave it as is.

However, I'm confused as to why we would need to manually set the form to valid. If you're copying over old values, I'm assuming those values pass all validations and thus if everything is bound correctly via ng-models in the DOM, wouldn't the form automatically be in a valid state?