Update documentation structure and start migrating to markdown (#934)

Starts structuring the documentation library usage into Tutorials, Guides, Explanations and Reference.
Continues migrating new docs from rst to markdown.
Extends the test framework discovery mocks to allow easy writing and testing of code examples.

kasa/deviceconfig.py

@@ -1,10 +1,35 @@
-"""Module for holding connection parameters.
+"""Configuration for connecting directly to a device without discovery.
+
+If you are connecting to a newer KASA or TAPO device you can get the device
+via discovery or connect directly with :class:`DeviceConfig`.
+
+Discovery returns a list of discovered devices:
+
+>>> from kasa import Discover, Credentials, Device, DeviceConfig
+>>> device = await Discover.discover_single(
+>>>     "127.0.0.3",
+>>>     credentials=Credentials("myusername", "mypassword"),
+>>>     discovery_timeout=10
+>>> )
+>>> print(device.alias)  # Alias is None because update() has not been called
+None
+
+>>> config_dict = device.config.to_dict()
+>>> # DeviceConfig.to_dict() can be used to store for later
+>>> print(config_dict)
+{'host': '127.0.0.3', 'timeout': 5, 'credentials': Credentials(), 'connection_type'\
+: {'device_family': 'SMART.TAPOBULB', 'encryption_type': 'KLAP', 'login_version': 2},\
+ 'uses_http': True}
+
+>>> later_device = await Device.connect(config=DeviceConfig.from_dict(config_dict))
+>>> print(later_device.alias)  # Alias is available as connect() calls update()
+Living Room Bulb
 
-Note that this module does not work with from __future__ import annotations
-due to it's use of type returned by fields() which becomes a string with the import.
-https://bugs.python.org/issue39442
 """
 
+# Note that this module does not work with from __future__ import annotations
+# due to it's use of type returned by fields() which becomes a string with the import.
+# https://bugs.python.org/issue39442
 # ruff: noqa: FA100
 import logging
 from dataclasses import asdict, dataclass, field, fields, is_dataclass