Add Initial Implementation of Open/CreateDataset/AddData

[aloisklink]

Adds the ability to open a dataset, create a dataset (including existing ones), and add data to it.

Documentation/unittests can be found in the README

[aloisklink]

I'm going to accept this, since it is basically a subset as nqminds/nqm-iot-database-utils except in Python.

Also, the main API is using an OOP approach, so instead of doing manager.addData(db, data), you do db.addData(data).

It will be very easy to make a functional approach, like above, ie:

def magick_function(db, *args, **kwargs):
    return db.magick_function(*args, **kwargs)