Add pagination to Studio's Files and Uploads page 

These changes represent the initial implementation of STUD-813 which adds pagination to the Files and Uploads page. @cahrens and @singingwolfboy, please pre-review this code since this is my first major change, and I want to be sure that I'm following best practices.

Note that I will be adding tests in my next commit, so this pull request will not be merged as is.