Add a granularity property to round to nearest 0.5C

[emoses]

I'm using FGLair-us with HA. Even though my thermostats display in F, I have to set the temp_type to C to have anything function properly. It appears that the actual adjust_temperature commands that the wifi units accept must be in increments of 0.5 C, but when I change the temperature in F in HA, AirCon currenly rounds to the nearest degree C, which means many temperature adjustments are no-ops (e.g. 70F to 69F results in no change, they both round to 21C).

Here's an example log:

hisense_ac    | I0327 04:41:57.734  mqtt_client.py:37] MQTT message Topic: hisense_ac/[redacted]/adjust_temperature/command, Payload b'20.555555555555554'
hisense_ac    | I0327 04:41:57.749  web_log.py:206] 192.168.2.161 [27/Mar/2023:04:41:57 +0000] "GET /local_lan/commands.json HTTP/1.1" 200 418 "-" "-"
hisense_ac    | I0327 04:42:09.753  mqtt_client.py:37] MQTT message Topic: hisense_ac/[redacted]/adjust_temperature/command, Payload b'20.0'
hisense_ac    | I0327 04:42:09.767  web_log.py:206] 192.168.2.161 [27/Mar/2023:04:42:09 +0000] "GET /local_lan/commands.json HTTP/1.1" 200 418 "-" "-"
hisense_ac    | I0327 04:42:10.790  query_handlers.py:139] Decrypted: {"seq_no":96,"data":{"name":"adjust_temperature","value":200}}
hisense_ac    | I0327 04:42:10.794  web_log.py:206] 192.168.2.161 [27/Mar/2023:04:42:10 +0000] "POST /local_lan/property/datapoint.json HTTP/1.1" 200 150 "-" "-"
hisense_ac    | I0327 04:42:16.766  mqtt_client.py:37] MQTT message Topic: hisense_ac/[redacted]/adjust_temperature/command, Payload b'21.11111111111111'
hisense_ac    | I0327 04:42:16.786  web_log.py:206] 192.168.2.161 [27/Mar/2023:04:42:16 +0000] "GET /local_lan/commands.json HTTP/1.1" 200 418 "-" "-"
hisense_ac    | I0327 04:42:19.773  query_handlers.py:139] Decrypted: {"seq_no":97,"data":{"name":"adjust_temperature","value":210}}

To account for this, I've added a "granularity" property that will round to the nearest 0.5C before the precision is applied. This fixes the problem for me.

[emoses]

Since precision only makes sense if the property is an int anyway, I've moved this to the int clause above

[emoses]

No reason to check for "." here, if it's an int value that doesn't have a decimal place the float logic won't affect it.

[emoses]

Closed in favor of #222