Graphql filters isOngoing, isPast and isFuture are not time aware.

[davola]

There is a problem when trying to filter an entry using the isOngoing, isPast and isFuture filters on an graphql query.
It happens that this filters only check for the date of the entry, not having into account the actual time (hs/min/secs).

I have created a PR here with a suggested fix to improve the resolution of this filters to became time aware as well.

Thanks!