Parameter Presets in wdl-ci configuration

[williamrowell]

It would be nice to be able to set Parameter Presets for workflows launched by wdl-ci, maybe like:

  "engines": {
    "mycromwellengine": {
      "key": "mycromwellengine",
      "enabled": true,
      "name": "",
      "parameter_preset": "wdl-ci"
    }
  }