increase sx1272 max power

+#define MAX_POWER 27
 // if we use 20 we are limited to 1% duty cycle or hw might overheat.  For continuous operation set a limit of 17
+// In theory up to 27 dBm is possible, but the modules installed in most radios can cope with a max of 20.  So BIG WARNING
+// if you set power to something higher than 17 or 20 you might fry your board.

src/mesh/RF95Interface.cpp

@@ -3,8 +3,10 @@
 #include "RadioLibRF95.h"
 #include <configuration.h>
 
-#define MAX_POWER 20
+#define MAX_POWER 27
 // if we use 20 we are limited to 1% duty cycle or hw might overheat.  For continuous operation set a limit of 17
+// In theory up to 27 dBm is possible, but the modules installed in most radios can cope with a max of 20.  So BIG WARNING
+// if you set power to something higher than 17 or 20 you might fry your board.
 
 #define POWER_DEFAULT 17 // How much power to use if the user hasn't set a power level