DCP RemoteDataSet and RemoteDataPattern return None

[wiwichips]

Example:

>>> my_rds = dcp.compute.RemoteDataPattern('http://localhost:12345/{slice}', 5)
>>> print(my_rds)
None

Instead, this should return a proxied object to the JavaScript RemoteDataPattern object instantiated from the call

Same issue with RemoteDataSet

[Xmader]

This might be fixed by 37f83ff.