Updated all comments for while (!Serial) additions to serial-based examples

libraries/Ethernet/examples/DhcpAddressPrinter/DhcpAddressPrinter.ino

@@ -9,7 +9,7 @@
  * Ethernet shield attached to pins 10, 11, 12, 13
  
  created 12 April 2011
- modified 2 Apr 2012
+ modified 9 Apr 2012
  by Tom Igoe
  
  */
@@ -31,8 +31,9 @@ void setup() {
  // Open serial communications and wait for port to open:
   Serial.begin(9600);
   // this check is only needed on the Leonardo:
-  while (!Serial) ;
- ;
+   while (!Serial) {
+    ; // wait for serial port to connect. Needed for Leonardo only
+  }
 
   // start the Ethernet connection:
   if (Ethernet.begin(mac) == 0) {