Bring API to working state for GET request

Several changes here:

- Fixed a couple minor syntax issues in the `index.php` script.
- Added the `github_handle` migration so the user table would work
  with the current `User` model and `UserService`.
- Modified the puppet manifests to expose mysql to the host machine.
  This was done to use tools like SequelPro to access the database.
- Fixed the environment discrepancy of `dev` vs `development`
- Added an `.htaccess` file to allow slim to work with pretty
  routing.