Global Former overhaul

## Make Former framework agnostic
#### Not up to date, things work actually better than this

- [x] Abstract Former's app dependency
- [x] Merge the `legacy`, `composer` and `agnostic` branches

### Laravel 3

- [x] Static facade
- [x] Markup
- [x] Populating
- [x] Repopulating
- [x] Configuration file
- [x] Custom configuration file
- [x] Localization
- [x] Errors handling
- [x] Live validation

### Laravel 4

- [x] Static facade
- [x] Markup
- [x] Populating
- [x] Repopulating
- [x] Configuration file
- [x] Custom configuration file
- [x] Localization
- [x] Errors handling
- [x] Live validation

### Stand-alone

- [x] Static facade
- [x] Markup
- [x] Populating
- [ ] Repopulating
- [ ] Configuration file
- [ ] Custom configuration file
- [ ] Localization
- [ ] Errors handling
- [ ] Live validation

## Refactoring

- [ ] Refactor groups to allow multi-fields groups
- [ ] Redo the whole checkbox thing, with the above multi-fields feature

## Additional features

- [x] Chainable actions block
- [x] Chainable buttons on actions blocks
- [x] Chainable Live Validation rules
- [x] Raw fields
- [ ] Widgets _ala_ Symfony / custom Field types
- [ ] Add classes to control groups

## In other news

- [ ] Clean up and reorganize Former's README
- [ ] Rewrite and update the API