Add feature flags and missing #includes.

These are needed to compile on some strict Linuxes.

src/misc_tools.c

@@ -20,9 +20,12 @@
  *
  */
 
+#define _POSIX_C_SOURCE 200809L
+#define _XOPEN_SOURCE 500
 #include <stdlib.h>
 #include <ctype.h>
 #include <string.h>
+#include <strings.h>
 #include <time.h>
 #include <limits.h>
 #include <dirent.h>