Make opening_hours less detailed

[habi]

I think it would be sufficient to have five minutes intervals for the opening_hours selector.
The way it is now one nearly gets a cramp when adding complicated time schedules...

[habi]

Here's the selector from Maps.Me with 5-minute intervals.

[and01]

This is actually a bug in the date/timer picker component.

See mmazzarolo/react-native-modal-datetime-picker#56

[sfkeller]

Hi Habi, Thanks for the issue. You're right; this is not adequate UX. Pull requests are welcome :-).