Fix one-second warning period for notifications

Adresses GitHub issue #204, the interactive part.

Signed-off-by: Lars Henriksen <LarsHenriksen@get2net.dk>
Signed-off-by: Lukas Fleischer <lfleischer@calcurse.org>

src/dmon.c

@@ -188,7 +188,7 @@ void dmon_start(int parent_exit_status)
 			DMON_ABRT(_("error loading next appointment\n"));
 
 		left = notify_time_left();
-		if (left > 0 && left < nbar.cntdwn
+		if (left > 0 && left <= nbar.cntdwn
 		    && notify_needs_reminder()) {
 			DMON_LOG(_("launching notification at %s for: \"%s\"\n"),
 				 nowstr(), notify_app_txt());