Allow to set autoTopicCreationOverride at PulsarNamespace object. #68

Hey,

First of all, congrats for your awesome work in the Pulsar space and this cool operator, very useful!

We think it would make sense to enrich the PulsarNamespace object with the "autoTopicCreationOverride" so there is more granularity in how to manage Topics per Pulsar Namespace.

So it would be good to have an specifc field for it, or maybe have a more generic spec.config.custom filed where we could place some specific PulsarNamespace options.

Similar to what you have done for the PulsarProxy object: https://github.com/streamnative/charts/blob/branch-pulsar-operator-0.12.3/charts/pulsar-operator/crds/pulsar.streamnative.io_pulsarproxies.yaml#L1227

Again, awesome work.

Cheers!