ui: show ages in the originator's timezone

This affects the tooltip showing the full time and the case when a date
is sufficiently old to be shown in full rather than as an offset.

Signed-off-by: John Keeping <john@keeping.me.uk>
diff --git a/ui-shared.h b/ui-shared.h
index 707cec9..e42f13a 100644
--- a/ui-shared.h
+++ b/ui-shared.h
@@ -63,7 +63,7 @@
 extern void cgit_vprint_error(const char *fmt, va_list ap);
 extern const struct date_mode *cgit_date_mode(const char *format);
 extern void cgit_print_date(time_t secs, const char *format, int local_time);
-extern void cgit_print_age(time_t t, time_t max_relative);
+extern void cgit_print_age(time_t t, int tz, time_t max_relative);
 extern void cgit_print_http_headers(void);
 extern void cgit_redirect(const char *url, bool permanent);
 extern void cgit_print_docstart(void);