Added a macro and button definition for controlling fan

.pronsolerc.example

 # Sample .pronsolerc file - copy this into your home directory and rename it to .pronsolerc
 !print "Loaded " + self.rc_filename
+
 macro loud
   !if self.p.loud:
     !self.p.loud = 0
@@ -10,3 +11,17 @@ macro loud
     !if hasattr(self,"cur_button") and self.cur_button is not None: 
       !self.onecmd('button %d "loud (on)" /c yellow loud' % self.cur_button)
 button 0 "loud (off)" /c "green" loud
+
+macro fan
+  !global _fan
+  !if '_fan' in globals() and _fan:
+    !_fan = 0
+    M107
+    !if hasattr(self,"cur_button") and self.cur_button is not None: 
+      !self.onecmd('button %d "fan (off)" /c green fan' % self.cur_button)
+  !else:
+    !_fan = 1
+    M106
+    !if hasattr(self,"cur_button") and self.cur_button is not None: 
+      !self.onecmd('button %d "fan (on)" /c yellow fan' % self.cur_button)
+button 1 "fan (off)" /c "green" fan