Add CodeSchool & Location resources to ActiveAdmin

[hpjaj]

Feature

Why is this feature being added?

Gives admins the ability to conduct CRUD actions on the CodeSchool model. Currently this has to be done through prod's rails console.

What should your feature do?

Here are the ActiveAdmin docs: https://activeadmin.info/documentation.html

Here is a sample implementation of a Resource in our codebase: https://github.com/OperationCode/operationcode_backend/blob/master/app/admin/user.rb

• [ ] Adds a Resource for CodeSchool to ActiveAdmin
• [ ] Adds a Resource for Location to ActiveAdmin
• [ ] Smoke tests CRUD for CodeSchool and Location records