[MEDIUM] many cleanups in the time functions

Now, functions whose name begins with '__tv_' are inlined. Also,
'tv_ms' is used as a prefix for functions using milliseconds.
diff --git a/src/backend.c b/src/backend.c
index f096874..b357646 100644
--- a/src/backend.c
+++ b/src/backend.c
@@ -542,7 +542,7 @@
 	}
 
 	if (s->be->contimeout)
-		tv_delayfrom(&s->req->cex, &now, s->be->contimeout);
+		tv_ms_add(&s->req->cex, &now, s->be->contimeout);
 	else
 		tv_eternity(&s->req->cex);
 	return SN_ERR_NONE;  /* connection is OK */
@@ -672,7 +672,7 @@
 	case SRV_STATUS_QUEUED:
 		/* FIXME-20060503 : we should use the queue timeout instead */
 		if (t->be->contimeout)
-			tv_delayfrom(&t->req->cex, &now, t->be->contimeout);
+			tv_ms_add(&t->req->cex, &now, t->be->contimeout);
 		else
 			tv_eternity(&t->req->cex);
 		t->srv_state = SV_STIDLE;