Incomplete output of expanded services

[ridoo]

To create a valid expanded output of services, we need

• to count available parameters, i.e. add an implementation of CountingMetadataService
• add supported datasets incl. mimetypes

For example

[
  {
    "id": "1",
    "label": "My RESTful Dataset Service",
    "extras": [
      "license"
    ],
    "version": "2.0",
    "type": "Thin DB access layer service.",
    "supportedMimeTypes": {
      "count": [
        "application/json"
      ],
      "text": [
        "application/json"
      ],
      "measurement": [
        "image/png",
        "application/pdf",
        "application/json",
        "text/csv",
        "application/zip"
      ]
    },
    "supportsFirstLatest": true,
    "quantities": {
      "categories": 1,
      "features": 2,
      "offerings": 2,
      "phenomena": 1,
      "platforms": 2,
      "datasets": 4,
      "procedures": 2
    }
  }
]