Added keywords for new libraries, rearranged and modified Due and USB examples

Renamed Leonardo Only examples folder to USB. Modified keyboard and
Mouse examples to indicate Due compatibility.

Minor modifications to Due examples to conform with existing example
sketches.

Added keywords to for Audio, Scheduer, and USBHost libraries.

build/shared/examples/09.USB/KeyboardAndMouseControl/KeyboardAndMouseControl.ino

@@ -0,0 +1,96 @@
+
+/*
+  KeyboardAndMouseControl
+
+ For Leonardo and Due boards only.
+ 
+ Controls the mouse from five pushbuttons on an Arduino Leonardo.
+ 
+ Hardware:
+ * 5 pushbuttons attached to D2, D3, D4, D5, D6
+ 
+ 
+ The mouse movement is always relative. This sketch reads 
+ four pushbuttons, and uses them to set the movement of the mouse.
+ 
+ WARNING:  When you use the Mouse.move() command, the Arduino takes
+ over your mouse!  Make sure you have control before you use the mouse commands.
+ 
+ created 15 Mar 2012
+ modified 27 Mar 2012
+ by Tom Igoe
+ 
+ this code is in the public domain
+ 
+ */
+
+// set pin numbers for the five buttons:
+
+// set pin numbers for the five buttons:
+const int upButton = 2;     
+const int downButton = 3;        
+const int leftButton = 4;
+const int rightButton = 5;
+const int mouseButton = 6;
+
+void setup() { // initialize the buttons' inputs:
+  pinMode(upButton, INPUT);       
+  pinMode(downButton, INPUT);       
+  pinMode(leftButton, INPUT);       
+  pinMode(rightButton, INPUT);       
+  pinMode(mouseButton, INPUT);
+  
+  Serial.begin(9600);
+  // initialize mouse control:
+  Mouse.begin();
+  Keyboard.begin();
+}
+
+void loop() {
+  // use serial input to control the mouse:
+  if (Serial.available() > 0) {
+    char inChar = Serial.read();
+
+    switch (inChar) {   
+    case 'u':
+      // move mouse up
+      Mouse.move(0, -40);
+      break; 
+    case 'd':
+      // move mouse down
+      Mouse.move(0, 40);
+      break;
+    case 'l':
+      // move mouse left
+      Mouse.move(-40, 0);
+      break;
+    case 'r':
+      // move mouse right
+      Mouse.move(40, 0);
+      break;
+    case 'm':
+      // move mouse right
+      Mouse.click(MOUSE_LEFT);
+      break;
+    }
+  }
+
+  // use the pushbuttons to control the keyboard:
+  if (digitalRead(upButton) == HIGH) {
+    Keyboard.write('u'); 
+  }
+  if (digitalRead(downButton) == HIGH) {
+    Keyboard.write('d'); 
+  }
+  if (digitalRead(leftButton) == HIGH) {
+    Keyboard.write('l'); 
+  }
+  if (digitalRead(rightButton) == HIGH) {
+    Keyboard.write('r'); 
+  }
+  if (digitalRead(mouseButton) == HIGH) {
+    Keyboard.write('m'); 
+  }
+
+}
+