Set Resources requests/limits default limits

[NissesSenap]

Hey

As a happy beginner with nats it would be nice to get some decent default resources request/limits with the operator.
I know that I can put them down myself as defined in #236

I know setting defaults limits is hard due to that you don't know what kind of workload you want to run on nats but I personally think something small is better then nothing.

[jorgelon]

try with this in the helm chart

container:
  merge:
    resources:
      limits:
        memory: 128Mi
      requests:
        cpu: 10m
        memory: 50Mi