Remove cyclic dependency between str_array.h and r3.h

This also makes sure we dont get warnings regarding bool
redefinitions when building with clang.

include/r3.h

@@ -13,23 +13,14 @@
 #include <pcre.h>
 
 #ifdef HAVE_STDBOOL_H
-
-#include <stdbool.h>
-
-#else
-
-#if !defined(bool) && !defined(__cplusplus)
+#  include <stdbool.h>
+#elif !defined(bool) && !defined(__cplusplus)
 typedef unsigned char bool;
-#endif
-#ifndef false
+#  define bool bool /* For redefinition guards */
 #  define false 0
-#endif
-#ifndef true
 #  define true 1
 #endif
 
-#endif
-
 #include "str_array.h"
 #include "r3_slug.h"
 #include "memory.h"

include/str_array.h

@@ -8,9 +8,17 @@
 #ifndef STR_ARRAY_H
 #define STR_ARRAY_H
 
-#include "r3.h"
 #include "memory.h"
 
+#ifdef HAVE_STDBOOL_H
+#  include <stdbool.h>
+#elif !defined(bool) && !defined(__cplusplus)
+typedef unsigned char bool;
+#  define bool bool /* For redefinition guards */
+#  define false 0
+#  define true 1
+#endif
+
 typedef struct _str_array {
   R3_VECTOR(r3_iovec_t) slugs;
   R3_VECTOR(r3_iovec_t) tokens;