Career (Job) & Resource Rework

Main highlights of this commit:

- Changed internal Rails reference from Careers ==> Jobs (so model + controller have same name, etc.). Route to users will still be ../careers, but internally, we should handle as Jobs.
- Changed Resources model to ==> Resource - models should be singular for convention.
- Career edit page now setup with AJAX calls!
- Added new/create actions for Jobs / Resources + buttons on the ../edit pages for both.

Planning to write write tests and refactor some of this code later this week.

Let me know if you have any questions!