CC-2450:Phone home metric

- email is not required anymore.
- Send info box suppose to dispalys filelds only when thev
value is non-empty string. It wasn't diaplyng where the
value was 0(fixed).

airtime_mvc/application/models/Preference.php

@@ -332,7 +332,7 @@ class Application_Model_Preference
 
     	$outputString = "\n";
     	foreach($outputArray as $key => $out){
-    	    if(!empty($out)){
+    	    if($out != ''){
     		    $outputString .= $key.' : '.$out."\n";
     	    }
     	}