Implement timeouts per operation nature

[eddycharly]

This is an improvement proposal to implement timeouts per operation nature.

In practice different operations have different latency expectations and managing a single timeout (currently per step) sounds not ideal.

The timeout to create a resource for example should not be the same as the timeout to assert a reconciliation happened in an operator/controller.
Creating a resource is expected to be reasonably fast while a controller could take some time before the reconciliation is completed.

An operator creating a database could use a timeout of several minutes before the DB is up and running (probably check with an assertion on the status).
Creating the resource representing the database is a short operation though.

Supporting different timeouts per operation could be implemented with a config section like this:

timeouts:
  apply: 3s
  assert: 30s
  delete: 15s
  error: 20s

Each timeout will have a default value and timeouts should be overridable in a specific step if necessary.

[eddycharly]

Was implemented in #281