Add user store for app

[SpencerKaiser]

Pre-requisites

• I looked through both open and closed issues and did not find an existing bug.

Describe the solution you'd like

We should create a UserStore to eliminate the need for multiple pages/components to retrieve the info for a signed in user

We should also verify that this information is not better stored in local storage or already available via the cookie

Upon implementing this, we should go through and clean up all uses of the api/users/me endpoint in favor of this