Multiple action support

Breaking change: adding support of multiple actions.

For dispatch the request should include action field:

{
    "action": "export",
    "input": <here goes the original request as a JSON>
}

Would be release as version 0.3.0.

Possible configuration for "Export to PFB" in manifest:

  "sower": [
    {
      "name": "pelican-export",
      "action": "export",
      "container": {
        "name": "job-task",
        "image": "quay.io/cdis/pelican:0.1.1",
        "pull_policy": "Always",
        "env": [
          {
            "name": "DICTIONARY_URL",
            "valueFrom": {
              "configMapKeyRef": {
                "name": "manifest-global",
                "key": "dictionary_url"
              }
            }
          },
          {
            "name": "GEN3_HOSTNAME",
            "valueFrom": {
              "configMapKeyRef": {
                "name": "manifest-global",
                "key": "hostname"
              }
            }
          },
          {
            "name": "ROOT_NODE",
            "value": "case"
          }
        ],
        "volumeMounts": [
          {
            "name": "pelican-creds-volume",
            "readOnly": true,
            "mountPath": "/pelican-creds.json",
            "subPath": "config.json"
          },
          {
            "name": "peregrine-creds-volume",
            "readOnly": true,
            "mountPath": "/peregrine-creds.json",
            "subPath": "creds.json"
          }
        ],
        "cpu-limit": "1",
        "memory-limit": "12Gi"
      },
      "volumes": [
        {
          "name": "pelican-creds-volume",
          "secret": {
            "secretName": "pelicanservice-g3auto"
          }
        },
        {
          "name": "peregrine-creds-volume",
          "secret": {
            "secretName": "peregrine-creds"
          }
        }
      ],
      "restart_policy": "Never"
    }
  ]

Requires data-portal version >= 2.17.0.