[Nodedb-interop] Database shema of Nodewatcher

[Mitar]

Hi!

> The major point (and the reason we need this) is that nodewatcher v3
> schema needs to be easily extensible by modules. It should also enable
> automatic form generation and validation for this schema.

Yes, the main point is to use Django's automatic mechanisms
(model-view-controller) which can do many things by themselves. By that
it will be very easy to write new/additinal/slightly changed features,
while retaining the whole codebase. So it will not be necessary to write
everything from scratch just to change one small part of the system, but
you will just replace that part by something different or even just with
a class extending the original code class but with slightly different
functionality.

So we are using object-oriented programing both in code and schema.


Mitar