Updated Admin interface with full ng-material and unapprove button.

[audiodude]

Here is a screenshot:

Note that the drinks labelled 1 and 2 are first and second in the queue, respectively. When the first drinks starts being made, it will get a (!) icon, and the 2nd drink will now be 1st. These numbers should correspond to the numbers that users see on their phones.

[funrollloops]

Looks great!