Remove 'kohana' from media URLs

Summary:
Remove 'kohana' from media URLs
Update paths for new media urls

Test Plan:
- Check UI loads OK
- `./bin/behat -c application/tests/behat.yml -f progress application/tests/features/api.media.feature`

Reviewers: eyedol, shadowhand

Reviewed By: shadowhand

Differential Revision: https://phabricator.ushahidi.com/D251