Pass XBeeAddress64 objects as const references where possible

Previously, they were passed as normal references. Adding const does not
change the code in any way, but allows passing temporary objects as
well, so you can do:

    req.setAddress64(XBeeAddress64(0, 0xffff));

Or even just:

    req.setAddress64(0x0013A20012345678);

Author: matthijskooijman

XBee.cpp

@@ -1059,14 +1059,14 @@ ZBTxRequest::ZBTxRequest() : PayloadRequest(ZB_TX_REQUEST, DEFAULT_FRAME_ID, NUL
 	_option = ZB_TX_UNICAST;
 }
 
-ZBTxRequest::ZBTxRequest(XBeeAddress64 &addr64, uint16_t addr16, uint8_t broadcastRadius, uint8_t option, uint8_t *data, uint8_t dataLength, uint8_t frameId): PayloadRequest(ZB_TX_REQUEST, frameId, data, dataLength) {
+ZBTxRequest::ZBTxRequest(const XBeeAddress64 &addr64, uint16_t addr16, uint8_t broadcastRadius, uint8_t option, uint8_t *data, uint8_t dataLength, uint8_t frameId): PayloadRequest(ZB_TX_REQUEST, frameId, data, dataLength) {
 	_addr64 = addr64;
 	_addr16 = addr16;
 	_broadcastRadius = broadcastRadius;
 	_option = option;
 }
 
-ZBTxRequest::ZBTxRequest(XBeeAddress64 &addr64, uint8_t *data, uint8_t dataLength): PayloadRequest(ZB_TX_REQUEST, DEFAULT_FRAME_ID, data, dataLength) {
+ZBTxRequest::ZBTxRequest(const XBeeAddress64 &addr64, uint8_t *data, uint8_t dataLength): PayloadRequest(ZB_TX_REQUEST, DEFAULT_FRAME_ID, data, dataLength) {
 	_addr64 = addr64;
 	_addr16 = ZB_BROADCAST_ADDRESS;
 	_broadcastRadius = ZB_BROADCAST_RADIUS_MAX_HOPS;
@@ -1123,7 +1123,7 @@ uint8_t ZBTxRequest::getOption() {
 	return _option;
 }
 
-void ZBTxRequest::setAddress64(XBeeAddress64& addr64) {
+void ZBTxRequest::setAddress64(const XBeeAddress64& addr64) {
 	_addr64 = addr64;
 }
 

XBee.h

@@ -1188,8 +1188,8 @@ class ZBTxRequest : public PayloadRequest {
 	/**
 	 * Creates a unicast ZBTxRequest with the ACK option and DEFAULT_FRAME_ID
 	 */
-	ZBTxRequest(XBeeAddress64 &addr64, uint8_t *payload, uint8_t payloadLength);
-	ZBTxRequest(XBeeAddress64 &addr64, uint16_t addr16, uint8_t broadcastRadius, uint8_t option, uint8_t *payload, uint8_t payloadLength, uint8_t frameId);
+	ZBTxRequest(const XBeeAddress64 &addr64, uint8_t *payload, uint8_t payloadLength);
+	ZBTxRequest(const XBeeAddress64 &addr64, uint16_t addr16, uint8_t broadcastRadius, uint8_t option, uint8_t *payload, uint8_t payloadLength, uint8_t frameId);
 	/**
 	 * Creates a default instance of this class.  At a minimum you must specify
 	 * a payload, payload length and a 64-bit destination address before sending
@@ -1200,7 +1200,7 @@ class ZBTxRequest : public PayloadRequest {
 	uint16_t getAddress16();
 	uint8_t getBroadcastRadius();
 	uint8_t getOption();
-	void setAddress64(XBeeAddress64& addr64);
+	void setAddress64(const XBeeAddress64& addr64);
 	void setAddress16(uint16_t addr16);
 	void setBroadcastRadius(uint8_t broadcastRadius);
 	void setOption(uint8_t option);