Load default Kohana modules using Composer, refs T197

Summary:
- cache
- database
- image
- minion
- orm
- unittest
- system (core)

Test Plan:
After patching, upgrade with:

  git submodule sync
  git clean -fd modules/
  git clean -fd system/
  composer update

Try app. If it works, all is well.

Reviewers: rjmackay

Reviewed By: rjmackay

Subscribers: dkobia

Maniphest Tasks: T197

Differential Revision: https://phabricator.ushahidi.com/D53