Profile page, starred openings

**Note: run `rake db:migrate` after merging this PR!**  

#### Profile

- Can edit user

#### Project

- Create, delete projects
- Delete openings

#### Favorites

- Users can now "star" (i.e. favorite) openings

##### The `star` directive

To star an opening, use the `star` directive, found in `angular/directives`. This directive allows you to type `<span star opening-id="{{opening.id}}">Any text here</span>`, which will automatically create a clickable link that toggles the "starred" status of the given opening (for the current user). Right now, it adds the class `starred` to the `span` element if the user has favorited the opening. I wrote a bit of CSS in `style.css` that bolds anything that's `.star.starred`, but we probably want to have it be a nice star icon that's filled in when starred, and empty when not.   

Check `views/templates/project.html` for an example (line 22).