The schema lists post_id as required, but the official TypeScript
client types it as `string | null`. A null would fail with a TypeError
and, unlike an unknown update type, TypeError is not caught while
parsing updates.
UpdateType already had comment_created, comment_edited,
comment_removed and bot_admin_permissions_changed, but ModelFactory
had no models for them and threw "Unknown or unsupported update type".
Adds the models from schema 0.0.33, maps them in createUpdate() and
adds on*() shortcuts to UpdateDispatcher and MaxBotManager.
Timofey