Extracted lowerVolume to seperate file

src/main.cpp

@@ -125,45 +125,7 @@ void loop()
   // Remote A - Significantly Lower Volume
   if (debounceRead(REMOTE_A))
   {
-
-    // Check if we volume is already lowered
-    if (oldUserVolume > userVolume)
-    {
-
-      // If it is lowered - restore it
-      // Check if max volume has changed since lowering
-      if (oldUserVolume > maxVolume)
-      {
-        // If the max volume has been lowered since lowering, then set the user volume to the new max volume
-        userVolume = maxVolume;
-
-        for (int i = 0; i < maxVolume; i++)
-        {
-          potIncrement();
-        }
-      }
-      else
-      {
-        // If the max volume hasn't changed then, or the old user volume is lower than the new max - restore it to where it was
-        userVolume = oldUserVolume;
-
-        for (int i = 0; i < oldUserVolume; i++)
-        {
-          potIncrement();
-        }
-      }
-    }
-    else
-    {
-      // This is if the user is not lowered and is aksing to be lowered
-      for (int i = 0; i < userVolume - 10; i++)
-      {
-        potDecrement();
-      }
-
-      oldUserVolume = userVolume;
-      userVolume -= 10;
-    }
+    lowerVolume(&userVolume, &oldUserVolume, maxVolume);
   }
 
   // Remote B - Volume Up