Fixes#39
### Motivation
The match expression for the "app" label was incorrect breaking the antiaffinity since they would never match. Fixing this makes the podAntiAffinity work, but now requires at least N nodes to be in the cluster where N = largest replica set with affinity. Added the option to set the affinity type to preferredDuringSchedulingIgnoredDuringExecution where it will try to follow the affinity, but will still deploy a pod if it needs to break it.
### Modifications
- Fixed app matchExpression
- Added option to set the affinity type
- bumped chart version
### Verifying this change
- [X] Make sure that the change passes the CI checks.
* Add 'http' port specification to zookeeper statefulset
This makes the zookeeper spec inline with the other statefulset specs
in this chart and it provides a port target for custom podMonitors
* Added PodMonitors for bookie, broker, proxy, and zookeeper
New PodMonitors are needed for prometheus-operator to pickup scrape
targets.
Defaults to disabled so users need to opt in to deploy
* Added Apache license info to podmonitor yamls