Orderer v3: remove kafka support

In v3 we will remove support for kafka as an orderer consensus protocol.

- [x] Disable kafka as a consensus protocol
- [x] Remove all integration tests that use kafka
- [x] Move integration tests that do consensus type migration to raft, use solo-raft migration
- [x] Remove kafka from integration tests infrastructure
- [x] Remove kafka code from orderer / consensus
- [x] Clean up the code for kafka to raft migration, but keep some features of it that may be useful for migration from protocol to protocol (e.g. raft -> bft)
- [x] Remove kafka from local config objects and methods
- [x] Remove kafka from (shared) channel config objects and methods
- [x] Remove (or depricate) kafka from protos
- [x] Remove kafka from configtxgen
- [x] Remove kafka dependencies from build infrastructure - docker-thirdparty
- [x] Update documentation
- [x] Remove kafka from fabric-config project [PR 59](https://github.com/hyperledger/fabric-config/pull/59)
- [ ] Revise/review SDKs to work with new protos that do not include kafka

In Epic: #3511