Code cleanup/rationalize mcglobals, cookie and User service about materialscommons.org

[gtarcea]

Step one completed. Most of the code for calling into the service has been consolidated into a new AngularJS service called mcapi. This service will also allow us to centralize many of the changes to the state changing variables and cookies. Most (hopefully all) of the redundancy between the cookie, User and mcglobals can be eliminated.

However udcontroller for uploads/downloads uses the $http service in a different way. Before this transition can be completed this usage needs to be tested against the mcapi interface, and then ported when working.

[gtarcea]

Comment for close: One set of state for the user in the User service. The service uses a cookie to persist its data.