general cleanup: rm unused config.h, add license info to device.c/h, add a couple compiler options and fix warnings

src/toxic.c

@@ -20,14 +20,14 @@
  *
  */
 
-#ifdef HAVE_CONFIG_H
-#include "config.h"
-#endif
-
 #ifndef SIGWINCH
 #define SIGWINCH 28
 #endif
 
+#ifndef SIGINT
+#define SIGINT 2
+#endif
+
 #include <curses.h>
 #include <errno.h>
 #include <stdio.h>