Make patcher parameters flexible

This MR changes the way patchers are configured:

Now a patcher definition takes 3 arguments:

1. type: patcher type, e.g. ReplicaPatcher.
2. resource: Kuberntes resources to be patched
3. config: a map containing all configuration parameters for the specific patcher

This makes it possible to improve the configurability of the NumNestedGroupsLoadGeneratorReplicaPatcher and the NumSensorsLoadGeneratorReplicaPatcher.

For example:

- type: "NumSensorsLoadGeneratorReplicaPatcher"
  resource: "uc1-load-generator-deploym ent.yaml"
  config:
    loadGenMaxRecords: "15000"

Closes #233 (closed)