feat: add CMR500 class

The CMR500 works the same as the CMR1000

pyBrematic/devices/intertechno/CMR500.py

@@ -0,0 +1,12 @@
+# -*- coding: utf-8 -*-
+# Reference: https://github.com/Power-Switch/PowerSwitch_Android/blob/master/Smartphone/src/main/java/eu/power_switch/obj/receiver/device/intertechno/CMR500.java
+# Since this is a dimmer, I am not sure if this code also supports dimming or only switchig.
+
+from .CMR1000 import CMR1000
+
+
+class CMR500(CMR1000):
+    """Device class for the Intertechno CMR-500 switch"""
+
+    def __init__(self, system_code, unit_code):
+        super().__init__(system_code, unit_code)