Simplify API documentation by using doctests (#73)

* Add doctests to SmartBulb

* Add SmartDevice doctests, cleanup README.md

* add doctests for smartplug and smartstrip

* add discover doctests

* Fix bulb mock

* add smartdimmer doctests

* add sphinx-generated docs, cleanup readme a bit

* remove sphinx-click as it does not work with asyncclick

* in preparation for rtd hooking, move doc deps to be separate from dev deps

* pytestmark needs to be applied separately for each and every file, this fixes the tests

* use pathlib for resolving relative paths

* Skip discovery doctest on python3.7

The code is just fine, but some reason the mocking behaves differently between 3.7 and 3.8.
The latter seems to accept a discrete object for asyncio.run where the former expects a coroutine..

kasa/smartbulb.py

@@ -23,53 +23,69 @@ TPLINK_KELVIN = {
 class SmartBulb(SmartDevice):
     """Representation of a TP-Link Smart Bulb.
 
-    Usage example:
-    ```python
-    p = SmartBulb("192.168.1.105")
-    await p.update()
+    To initialize, you have to await :func:`update()` at least once.
+    This will allow accessing the properties using the exposed properties.
 
-    # print the devices alias
-    print(p.alias)
+    All changes to the device are done using awaitable methods,
+    which will not change the cached values, but you must await :func:`update()` separately.
 
-    # change state of bulb
-    await p.turn_on()
-    await p.update()
-    assert p.is_on
-    await p.turn_off()
-
-    # query and print current state of plug
-    print(p.state_information)
-
-    # check whether the bulb supports color changes
-    if p.is_color:
-        print("we got color!")
-        # set the color to an HSV tuple
-        await p.set_hsv(180, 100, 100)
-        await p.update()
-        # get the current HSV value
-        print(p.hsv)
-
-    # check whether the bulb supports setting color temperature
-    if p.is_variable_color_temp:
-        # set the color temperature in Kelvin
-        await p.set_color_temp(3000)
-        await p.update()
-
-        # get the current color temperature
-        print(p.color_temp)
-
-    # check whether the bulb is dimmable
-    if p.is_dimmable:
-        # set the bulb to 50% brightness
-        await p.set_brightness(50)
-        await p.update()
-
-        # check the current brightness
-        print(p.brightness)
-    ```
-
-    Errors reported by the device are raised as SmartDeviceExceptions,
+    Errors reported by the device are raised as :class:`SmartDeviceException`s,
     and should be handled by the user of the library.
+
+    Examples:
+        >>> import asyncio
+        >>> bulb = SmartBulb("127.0.0.1")
+        >>> asyncio.run(bulb.update())
+        >>> print(bulb.alias)
+        KL130 office bulb
+
+        Bulbs, like any other supported devices, can be turned on and off:
+
+        >>> asyncio.run(bulb.turn_off())
+        >>> asyncio.run(bulb.turn_on())
+        >>> asyncio.run(bulb.update())
+        >>> print(bulb.is_on)
+        True
+
+        You can use the is_-prefixed properties to check for supported features
+        >>> bulb.is_dimmable
+        True
+        >>> bulb.is_color
+        True
+        >>> bulb.is_variable_color_temp
+        True
+
+        All known bulbs support changing the brightness:
+
+        >>> bulb.brightness
+        30
+        >>> asyncio.run(bulb.set_brightness(50))
+        >>> asyncio.run(bulb.update())
+        >>> bulb.brightness
+        50
+
+        Bulbs supporting color temperature can be queried to know which range is accepted:
+
+        >>> bulb.valid_temperature_range
+        (2500, 9000)
+        >>> asyncio.run(bulb.set_color_temp(3000))
+        >>> asyncio.run(bulb.update())
+        >>> bulb.color_temp
+        3000
+
+        Color bulbs can be adjusted by passing hue, saturation and value:
+
+        >>> asyncio.run(bulb.set_hsv(180, 100, 80))
+        >>> asyncio.run(bulb.update())
+        >>> bulb.hsv
+        (180, 100, 80)
+
+        If you don't want to use the default transitions, you can pass `transition` in milliseconds.
+        This applies to all transitions (turn_on, turn_off, set_hsv, set_color_temp, set_brightness).
+        The following changes the brightness over a period of 10 seconds:
+
+        >>> asyncio.run(bulb.set_brightness(100, transition=10_000))
+
     """
 
     LIGHT_SERVICE = "smartlife.iot.smartbulb.lightingservice"