[FrameworkBundle] Enable replacing of services

Now bundles can register services, that will replace other services/aliases, tagging system fits this scenarion quite well, and makes solution generic.

| Q             | A
| ------------- | ---
| Bug fix?      | no
| New feature?  | yes
| BC breaks?    | no
| Deprecations? | no
| Tests pass?   | yes
| Fixed tickets | #5920
| License       | MIT
| Doc PR        | symfony/symfony-docs#2228

- [x] Write Unit Tests
- [ ] Find good name for tag, and arguments
- [ ] Decide should this belong to DI component or FrameworkBundle?
- [x] If accepted write cookbook entry