Update cluster config from klaw ui/runtime

# What is currently missing?

Currently it is not possible to update cluster api configuration like adding a new cluster during runtime. After updating the config, a restart is required.

Ex config : Adding a new kafka cluster in cluster api config
dev1.kafkassl.keystore.location ....

# How could this be improved?

Make relevant changes so that cluster api config can be updated during runtime, without having to restart Klaw.

# Is this a feature you would work on yourself?

* [ ] I plan to open a pull request for this feature