Removed extra comparisons by converting original phrase to uppercase, then comparing

Removed previous multiple comparisons that were variations of capitalizing the same phrase by converting the original phrase to all uppercase and then comparing

src/org/thoughtcrime/securesms/service/SmsListener.java

@@ -48,8 +48,7 @@ public class SmsListener extends BroadcastReceiver {
 
     return
       message.getOriginatingAddress().length() < 7 &&
-      (messageBody.startsWith("//ANDROID:") || messageBody.startsWith("//Android:") || // Sprint Visual Voicemail
-       messageBody.startsWith("//android:") ||
+      (messageBody.toUpperCase().startsWith("//ANDROID:") || // Sprint Visual Voicemail
        messageBody.startsWith("//BREW:")); //BREW stands for “Binary Runtime Environment for Wireless"
   }