Add support for lightstrips (KL430) (#74)

* Preliminary support for light strips

* Add color temperature range and cleanup, thanks to @darkoppressor

* Use lightstrip instead of {led,light}strip consistently everywhere
* The cli flag is now --lightstrip

* add apidocs

* Add fixture file for KL430

Signed-off-by: Kevin Wells <darkoppressor@gmail.com>

* Add discovery support, expose effect and length of the strip

* use set_light_state instead of transition_light_state

* Add tests for lightstrip

* add doctests

* Add KL430 to supported devices in README

Co-authored-by: Kevin Wells <darkoppressor@gmail.com>

kasa/discover.py

@@ -9,6 +9,7 @@ from kasa.protocol import TPLinkSmartHomeProtocol
 from kasa.smartbulb import SmartBulb
 from kasa.smartdevice import SmartDevice, SmartDeviceException
 from kasa.smartdimmer import SmartDimmer
+from kasa.smartlightstrip import SmartLightStrip
 from kasa.smartplug import SmartPlug
 from kasa.smartstrip import SmartStrip
 
@@ -227,11 +228,19 @@ class Discover:
             and "get_dimmer_parameters" in info["smartlife.iot.dimmer"]
         ):
             return SmartDimmer
+
         elif "smartplug" in type_.lower() and "children" in sysinfo:
             return SmartStrip
+
         elif "smartplug" in type_.lower():
+            if "children" in sysinfo:
+                return SmartStrip
+
             return SmartPlug
         elif "smartbulb" in type_.lower():
+            if "length" in sysinfo:  # strips have length
+                return SmartLightStrip
+
             return SmartBulb
 
         raise SmartDeviceException("Unknown device type: %s", type_)