Merge pull request #14 from kholia/master

Fix M_PI related compilation isues on Linux

common/common.h

@@ -0,0 +1,3 @@
+#ifndef M_PI
+    #define M_PI 3.14159265358979323846
+#endif

decode_ft8.c

@@ -11,6 +11,7 @@
 #include "ft8/encode.h"
 #include "ft8/crc.h"
 
+#include "common/common.h"
 #include "common/wave.h"
 #include "common/debug.h"
 #include "fft/kiss_fftr.h"

gen_ft8.c

@@ -4,6 +4,7 @@
 #include <math.h>
 #include <stdbool.h>
 
+#include "common/common.h"
 #include "common/wave.h"
 #include "common/debug.h"
 #include "ft8/pack.h"

test.c

@@ -10,6 +10,7 @@
 #include "ft8/constants.h"
 
 #include "fft/kiss_fftr.h"
+#include "common/common.h"
 #include "common/debug.h"
 
 #define LOG_LEVEL LOG_INFO
@@ -155,4 +156,4 @@ int main()
     test4();
 
     return 0;
-}
+}