Add ventilation interface

libnymea/interfaces/interfaces.qrc

@@ -44,6 +44,7 @@
         <file>simpleclosable.json</file>
         <file>closable.json</file>
         <file>awning.json</file>
+        <file>ventilation.json</file>
         <file>shutter.json</file>
         <file>blind.json</file>
         <file>extendedclosable.json</file>

libnymea/interfaces/ventilation.json

@@ -0,0 +1,4 @@
+{
+    "description": "The ventilation interface is used for any sort of ventilation. It extends the \"power\" interface and thus can be turned on or off.",
+    "extends": "power"
+}