Added official HID definitions

Since the HID library adds some general HID definitions and structs, it is very useful to also include this in a custom library.
If you dupe the information you have problems of redeclaration.
Having those defintions inside the official HID library is essential for a good working additional  HID API.

Author: NicoHood

hardware/arduino/avr/libraries/HID/HID.cpp

@@ -30,7 +30,7 @@ int HID_::getInterface(uint8_t* interfaceCount)
 {
 	*interfaceCount += 1; // uses 1
 	HIDDescriptor hidInterface = {
-		D_INTERFACE(pluggedInterface, 1, 3, 0, 0),
+		D_INTERFACE(pluggedInterface, 1, USB_DEVICE_CLASS_HUMAN_INTERFACE, HID_SUBCLASS_NONE, HID_PROTOCOL_NONE),
 		D_HIDREPORT(descriptorSize),
 		D_ENDPOINT(USB_ENDPOINT_IN(pluggedEndpoint), USB_ENDPOINT_TYPE_INTERRUPT, USB_EP_SIZE, 0x01)
 	};

hardware/arduino/avr/libraries/HID/HID.h

@@ -40,6 +40,20 @@
 #define HID_REPORT_DESCRIPTOR_TYPE      0x22
 #define HID_PHYSICAL_DESCRIPTOR_TYPE    0x23
 
+// HID subclass HID1.11 Page 8 4.2 Subclass
+#define HID_SUBCLASS_NONE 0
+#define HID_SUBCLASS_BOOT_INTERFACE 1
+
+// HID Keyboard/Mouse bios compatible protocols HID1.11 Page 9 4.3 Protocols
+#define HID_PROTOCOL_NONE 0
+#define HID_PROTOCOL_KEYBOARD 1
+#define HID_PROTOCOL_MOUSE 2
+
+// Normal or bios protocol (Keyboard/Mouse) HID1.11 Page 54 7.2.5 Get_Protocol Request
+// "protocol" variable is used for this purpose.
+#define HID_BOOT_PROTOCOL	0
+#define HID_REPORT_PROTOCOL	1
+
 typedef struct
 {
   uint8_t len;      // 9