Fix emeter support for newer HS110 firmwares (#107)

* Add support for new-style emeter

This commit adds a straightforward dict-extending container,
which converts between the old and new keys of the get_emeter_realtime()
Furthermore the unit tests are converted to base on HS100
instead of HS110.

This is the first step to fix #103, other emeter-using functionality
has not yet been converted, only getting the current consumption.

* fix a couple of linting issues

* Convert new-style emeter values also for get_emeter_daily() and get_emeter_monthly()

* Adds a new 'kwh' parameter for those calls, which defaults to True
* This changes the behavior of bulbs emeter reporting, use False if you prefer the preciser values

pyHS100/smartplug.py

@@ -36,7 +36,6 @@ class SmartPlug(SmartDevice):
                  protocol: 'TPLinkSmartHomeProtocol' = None) -> None:
         SmartDevice.__init__(self, host, protocol)
         self.emeter_type = "emeter"
-        self.emeter_units = False
 
     @property
     def state(self) -> str: