Declare all configuration variables in optlist.h. Include that

instead of declaring them all over the place.  This uncovered type
errors:
(s_p_etu, adj_update): Defined long, sometimes declared int.  Kills
big endian machines where sizeof(long) != sizeof(int).  Change to
int.

(set_option, delete_option, optstrset, intset, floatset, doubleset,
longset, optionset, optiondel, worldxset): Change linkage to static.

src/server/idle.c

@@ -37,12 +37,12 @@
 #include "empthread.h"
 #include "proto.h"
 #include "prototypes.h"
+#include "optlist.h"
 
 /*ARGSUSED*/
 void
 player_kill_idle(void *argv)
 {
-    extern int max_idle;
     struct player *p;
     time_t now;
 

src/server/lostitem.c

@@ -40,12 +40,12 @@
 #include "lost.h"
 #include <stdio.h>
 #include "prototypes.h"
+#include "optlist.h"
 
 /*ARGSUSED*/
 void
 delete_lostitems(void *argv)
 {
-    extern int lost_items_timeout;
     time_t now;
     struct loststr lost;
     int n;

src/server/main.c

@@ -98,7 +98,6 @@ main(int argc, char **argv)
     int debug = 0;
     int op;
     char *config_file = NULL;
-    extern s_char *datadir;
     extern char *optarg;
     s_char tbuf[256];
 #ifdef POSIXSIGNALS

src/server/update.c

@@ -49,10 +49,6 @@ time_t update_time;
 void
 update_sched(void *argv)
 {
-    extern int s_p_etu;
-    extern int etu_per_update;
-    extern int adj_update;
-    extern int update_window;
     s_char *kw;
     int hour[2];
     int wind;