Use composer for autoloading, fixes T197

Summary:
- remove Pimple from `src/`, install with composer
- remove custom autoloader, register with composer

Test Plan:
- run `composer install`
- try app... if it works, nothing broke

Reviewers: rjmackay

Reviewed By: rjmackay

Subscribers: dkobia

Maniphest Tasks: T197

Differential Revision: https://phabricator.ushahidi.com/D47
Do not attempt to return file size if file does not exist, refs T79

Summary:
There is something deeper broken here... for_api should not attempt to return
the same information for a deleted media as for an active one.

Test Plan: ./bin/behat --config application/tests/behat.yml application/tests/features/api.media.feature --format progress

Reviewers: rjmackay

Reviewed By: rjmackay

Maniphest Tasks: T79

Differential Revision: https://phabricator.ushahidi.com/D52
DRY out index.php, moving most logic into app/kohana.php, fixes T205

Summary:
Moves a large block of Kohana boilerplate code into `application/kohana.php`.
Simplifies `application/tests/bootstrap.php` by using the new `kohana.php`.

Test Plan:
- open web app
- run phpunit and behat tests
- check that nothing breaks

Reviewers: rjmackay

Reviewed By: rjmackay

Maniphest Tasks: T205

Differential Revision: https://phabricator.ushahidi.com/D55
Enable running unit tests using "arc unit", refs T175

Test Plan:
Run any test using `arc unit`, eg:

  arc unit application/tests/classes/Util/BoundingBoxTest.php

Reviewers: rjmackay

Reviewed By: rjmackay

Maniphest Tasks: T175

Differential Revision: https://phabricator.ushahidi.com/D56
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
Attempting to fix Travis, refs T197
Maybe clean modules before update? Still trying to fix Travis... refs T197
Delete modules/cache directory (gently) fixes T197
Also unittest module (gently) remove refs T197
Remove remaining submodules
Reinstate email submodule
Update Config API to act on whole groups, instead of single keys, fixes T204

Summary:
- update namespace to place Entity and Repository together
- store Config group name in `@group` property
- add setGroup and getGroup methods to Config
- drop `config.format.hash` entirely
- update storage, routes, API, and JS to match backend changes

Test Plan:
- use settings page to modify config values
- run behat tests `application/tests/features/api.config.feature`

Reviewers: rjmackay

Reviewed By: rjmackay

Maniphest Tasks: T204

Differential Revision: https://phabricator.ushahidi.com/D54
step one: move modules/ushui to web
add new front matter and index
Add docco task for grunt
add ushahidiweb app and view
add Slim to composer, enable UshahidiWeb ns autoloader
update paths to match new structure
ushweb is no longer a module
add example htaccess