Re-organized nRF24L01.h file to place 'P' features in one

location. Changed some bit value interpretation.

Now auto-detects P-vaiants and is queryable. setDataRate now returns a
boolean indicating success or failure of the new data rate
request. The wide_band state indicator has been added and now tracks
the state, including on error fallback. Its now possible to query the
current data rate via getDataRate().

The AA retry duration has been changed to 1500us, which is the lowest
interval allowed when running at 250Kbs, with AA enabled, and 32-byte
packets.

nRF24L01.h

@@ -33,7 +33,6 @@
 #define STATUS      0x07
 #define OBSERVE_TX  0x08
 #define CD          0x09
-#define RPD         0x09
 #define RX_ADDR_P0  0x0A
 #define RX_ADDR_P1  0x0B
 #define RX_ADDR_P2  0x0C
@@ -74,17 +73,9 @@
 #define AW          0
 #define ARD         4
 #define ARC         0
-#define RF_DR_LOW   5
 #define PLL_LOCK    4
-#define RF_DR_HIGH  3
+#define RF_DR       3
 #define RF_PWR      6
-#define RF_PWR_LOW  1
-#define RF_PWR_HIGH 2
-#define RF_PWR_0DB  6
-#define RF_PWR_6DB  4
-#define RF_PWR_12DB 2
-#define RF_PWR_18DB 0
-#define LNA_HCURR   0
 #define RX_DR       6
 #define TX_DS       5
 #define MAX_RT      4
@@ -120,3 +111,15 @@
 #define FLUSH_RX      0xE2
 #define REUSE_TX_PL   0xE3
 #define NOP           0xFF
+
+/* Non-P omissions */
+#define LNA_HCURR   0
+
+/* P model memory Map */
+#define RPD         0x09
+
+/* P model bit Mnemonics */
+#define RF_DR_LOW   5
+#define RF_DR_HIGH  3
+#define RF_PWR_LOW  1
+#define RF_PWR_HIGH 2