New Hubs and Scopes API

The way to the new API (work in progress):

• Deprecate global API functions as defined in RFC

• Create new Scope2 and Client2 and api2.py and put new stuff there

• Move all the functions from Hub to Scope and make the existing Hub functions call the ones on the scope.

• Make all 40+ integrations work with Scope2 and Client2 and new api2.py.

• Make Scope call functions in Scope2, Client in Client2 and api.py in api2.py, make Hub a hollow shell that calls stuff in Scope2

• Make deprecation warnings in all Scope, Client and api.py and Hub functions that will be removed

Until here nothing should be breaking

• Remove deprecated functions in Scope, Client and api.py and Hub and rename Scope2 > Scope, Client2 > Client, api2.py > api.py. Remove Hub