[MAJOR] replaced all timeouts with struct timeval

The timeout functions were difficult to manipulate because they were
rounding results to the millisecond. Thus, it was difficult to compare
and to check what expired and what did not. Also, the comparison
functions were heavy with multiplies and divides by 1000. Now, all
timeouts are stored in timevals, reducing the number of operations
for updates and leading to cleaner and more efficient code.
diff --git a/include/types/task.h b/include/types/task.h
index 1fd78be..42699db 100644
--- a/include/types/task.h
+++ b/include/types/task.h
@@ -2,7 +2,7 @@
   include/types/task.h
   Macros, variables and structures for task management.
 
-  Copyright (C) 2000-2006 Willy Tarreau - w@1wt.eu
+  Copyright (C) 2000-2007 Willy Tarreau - w@1wt.eu
   
   This library is free software; you can redistribute it and/or
   modify it under the terms of the GNU Lesser General Public
@@ -38,7 +38,7 @@
 	struct ultree *wq;		/* NULL if unqueued, or back ref to the carrier node in the WQ */
 	int state;			/* task state : IDLE or RUNNING */
 	struct timeval expire;		/* next expiration time for this task, use only for fast sorting */
-	int (*process)(struct task *t);	/* the function which processes the task */
+	void (*process)(struct task *t, struct timeval *next);	/* the function which processes the task */
 	void *context;			/* the task's context */
 };