Temp: First version GCD module

[AnjaBruls]

No description provided.

[joente]

I think a re-build is required because I added a small change to th build script. (for running on alpine linux)

[joente]

I think we should expose three functions: get, upsert and delete and set the corresponding cmd value as default. We then can accept the following argumets:

Get:

["get", "*"]

Upsert:

["upsert", "*"]

Delete:

["delete", "*"]

This way the example can be as follow:

gcd.get({
      entities: [
          {
              key: {
                  id: 3,
                  namespace: 'test',
                  kind: 'Test',
                  parent: {
                      kind: 'Parent',
                      id: 2,
                      namespace: 'test',
                  }
              },
          }
      ],
      kind: 'Test',
      namespace: 'test',
}).then(|res| {
    res; // just return the response.
});