tuya/climate: Add support for halves precision if the sensor supports it

Devices may use a temperature divider of 2, in such case tuyah won't
properly handle its halves values using whole precision.

Fix this by checking if the device supports halves, and in such case to
return such precision

This needs PaulAnnekov/tuyaha#54

homeassistant/components/tuya/climate.py

@@ -23,6 +23,7 @@
     ATTR_TEMPERATURE,
     CONF_PLATFORM,
     CONF_UNIT_OF_MEASUREMENT,
+    PRECISION_HALVES,
     PRECISION_TENTHS,
     PRECISION_WHOLE,
     TEMP_CELSIUS,
@@ -159,6 +160,8 @@ def precision(self):
         """Return the precision of the system."""
         if self._tuya.has_decimal():
             return PRECISION_TENTHS
+        if self._tuya.has_halves():
+            return PRECISION_HALVES
         return PRECISION_WHOLE
 
     @property