Modal templates and directive for contacts manager

Includes modal templates for contact manager, add, and edit. A contact manager directive is created. The settings page is modified to include a `Contacts Manager` button which opens up the contacts manager modal. The contacts manager button is only shown when the user has an id/is logged in. The contact manager functionality is limited for now to show the list of contacts. A method is add to the contactData service api to return the contacts instance variable.