v0.2.0

Added

• Features -- Resolvers.
• Notebooks -- Resolvers.
• Documentation -- Resolvers. Files (omitted in v0.1.0).
• README -- Contributing section with Styling and Documentation subsections.

Changed

• Behaviour -- nexussdk.resources.create(...) is no more adding a @context if none is present.
• Notebooks -- pp = nxs.tools.pretty_print instead of def pp(x): print(json.dumps(x, indent=2)).