[POC]Drop "friendsofsymfony/user-bundle"

[wbloszyk]

Subject

I create this PR becouse current branch is working. Some of things is still must be move, rewrite or refactor.

I am targeting this branch, because this change are not respect BC.

Closes #1112.

Changelog

### Added
- Added some `Class::newMethod()` to do great stuff.

### Changed

### Deprecated

### Removed

### Fixed

### Security

Current status

• database: working
• admin panel: working
• login system: working
• change password: working
• send email: working
• resetting: working

Things to move

• Command
• Controller - do not needed in admin panel
• Events - only this require by admin
• Mailer
• Model
• Resources
  • doc
  • translations
    • bundle translations
    • validators
  • views
• Security
• Util
• Validator

To do

• Move translations
• Move events
• Update the changelog
• Update the tests
• Update the documentation
• Add an upgrade note

[SonataCI]

Could you please rebase your PR and fix merge conflicts?

[SonataCI]

Could you please rebase your PR and fix merge conflicts?

[jordisala1991]

Food for thoughts or things to discuss about:

• Do we need all the implementations on FosUser to have a user system?
• Do we want to use Swiftmailer?
• Maybe we should use Symfony guards instead of the implementation of Fos

[VincentLanglet]

A rebase is required