support glib native types instead of GstClockTime, since cannot support both easily

Signed-off-by: Marcin Kolny <marcin.kolny@flytronic.pl>
fixed proxy_query_caps that caused annoying warning

Signed-off-by: Marcin Kolny <marcin.kolny@flytronic.pl>
wrapped get_sticky_event

Signed-off-by: Marcin Kolny <marcin.kolny@flytronic.pl>