Initial pass at new style Users Controller 

Initial Controller routes and methods:

- [x] get all users
- [x] get single user
- [x] create user
- [x] update user
- [ ] delete user

Test coverage routes and methods:

- [ ] get all users
- [ ] get single user
- [ ] create user
- [ ] update user
- [ ] delete user
I kept the uppercase for `order` since that is how it is in the Codex: http://codex.wordpress.org/Class_Reference/WP_User_Query#Order_.26_Orderby_Parameters  Honestly, I am open to whatever here.