[ENHANCEMENT] Globalize cluster sizing values

[jonathanlukas]

Describe the use case:

When altering the zeebe.partitionCount, you always have to adjust the optimize.partitionCount as well.

Describe the enhancement/feature:

Instead of having zeebe.partitionCount, zeebe.replicationFactor and zeebe.clusterSize, offer these values globally so that every component that relies on these numbers can use them and is in sync.

Desired outcome and acceptance tests:

There is no more than one (globally accessible) section in the values.yaml that describe the cluster sizing.

[aabouzaid]

Related to: #320