Feat/channelization further work (microsoft#641)

* fix: refactor Instrument to avoid removing methods from channels

* Include channels in print_readable_snaphoot

* Fix: make locked channels a named tuple

That way you can access the names on the channellist via names as soon as they are locked

* Fix: channels add support for indexing from 1

many instruments have hardware channels that are indexed and start at 1

* Fix linting errors in channel

* fix typo

* Move print readable snapshot to instrument class where it belongs

* Fix: more channel annotation

* Improve error message

* pprint limit line lenght of header to max char

* pep8 line lenght

* Fix: channel remove support for oneindexed channels

* improve type annotation

* Optional -> Union

* add channels to api docs

* fix: make submodules nested

* add submodule attributes to base

* Replace namedtuple by dict

Make it possible to get channels by name even when not locked

* Add submodule to docstring

docs/api/public.rst

@@ -101,6 +101,8 @@ Instrument
    IPInstrument
    VisaInstrument
 
+   InstrumentChannel
+   ChannelList
 
 Plot
 ~~~~