Update HID.h with report types (#602)

Add missing #define statements when compared to AVR library.
Support for readbytes with a byte/uint8_t buffer

cores/arduino/USB/USBAPI.h

@@ -117,6 +117,7 @@ class Serial_ : public arduino::HardwareSerial, arduino::PluggableUSBModule
 	operator bool();
 
 	size_t readBytes(char *buffer, size_t length);
+	size_t readBytes( uint8_t *buffer, size_t length) { return readBytes((char *)buffer, length); }
 
 	// This method allows processing "SEND_BREAK" requests sent by
 	// the USB host. Those requests indicate that the host wants to

libraries/HID/HID.h

@@ -54,6 +54,11 @@
 #define HID_BOOT_PROTOCOL	0
 #define HID_REPORT_PROTOCOL	1
 
+// HID Request Type HID1.11 Page 51 7.2.1 Get_Report Request
+#define HID_REPORT_TYPE_INPUT   1
+#define HID_REPORT_TYPE_OUTPUT  2
+#define HID_REPORT_TYPE_FEATURE 3
+
 typedef struct
 {
   uint8_t len;      // 9