Add end-of-game dumplogs

This is based on the "new" dumplog patch for 3.6.0, by Maxime Bacoux.

Define DUMPLOG to enable. By default only enabled for the TTY linux.

include/sys.h

@@ -15,6 +15,9 @@ struct sysopt {
     char *shellers;   /* like wizards, for ! command (-DSHELL); also ^Z */
     char *genericusers; /* usernames that prompt for user name */
     char *debugfiles; /* files to show debugplines in. '*' is all. */
+#ifdef DUMPLOG
+    char *dumplogfile; /* where the dump file is saved */
+#endif
     int env_dbgfl;    /*  1: debugfiles comes from getenv("DEBUGFILES")
                        *     so sysconf's DEBUGFILES shouldn't override it;
                        *  0: getenv() hasn't been attempted yet;