Added WiFiCheck example to Bridge Library

hardware/arduino/avr/libraries/Bridge/examples/WiFiCheck/WiFiCheck.ino

@@ -0,0 +1,53 @@
+/*
+  Arduino Yun Wireless Config Check
+ 
+ Checks the wireless state of Arduino Yun by calling
+ the linux command iwconfig.
+ 
+ Upload this to an Arduino Yun via serial (not WiFi) 
+ then open the serial monitor to see the status of
+ your Yun's WiFi connection. If it's connected to 
+ a wireless network, the ESSID (name) of that network
+ and the signal strength will appear.
+ 
+ The circuit:
+ * Arduino Yun
+ 
+ created 22 May 2013
+ by Tom Igoe
+ 
+ This example code is in the public domain.
+ */
+
+#include <Process.h>
+
+void setup() {
+  Serial.begin(9600);  // initialize serial communication
+  while(!Serial);      // do nothing until the serial monitor is opened
+ 
+  pinMode(13,OUTPUT);  
+  digitalWrite(13, LOW);  
+  Bridge.begin();      // make contact with the linux processor
+  digitalWrite(13, HIGH); 
+
+  delay(2000);         // wait 2 seconds
+
+  Process wifiCheck;    // initialize a new process
+
+
+  wifiCheck.begin("iwconfig");        // command you want to run
+  wifiCheck.addParameter("wlan0");    // parameter of the command
+  wifiCheck.run();                    // run the command
+
+  // while there's any characters coming back from the 
+  // process, print them to the serial monitor:
+  while (wifiCheck.available() > 0) {
+    char thisChar = wifiCheck.read();
+    Serial.print(thisChar);
+  }
+}
+
+void loop() {
+  // nothing to do here.
+}
+