Deprecate ConsoleRunner

[morozov]

The class serves two purposes:

1. Helping users bootstrap a CLI application. The class is not extensible by any means, so if a user needs to modify the CLI application, they will have to copy the code from the DBAL to their project. It's better if they start by implementing the application from scratch using the documentation.
2. Registering all DBAL-supplied commands in one call. The DBAL supplies a single non-deprecated command. Furthermore, the ORM doesn't use this class when registering DBAL commands, meaning that it's not that important.

See #5337 (review) for more details.

[derrabus]

The documentation on how to set up the console needs to be updated if we don't want people to use ConsoleRunner anymore.