Use HTML5 datetime picker in bulk action forms

Thanks for opening this @erlarese!

I'm going to tweak the title and description a bit to make this a feature request.

I'll go ahead and make this change and release a new version shortly. It's nice and simple and will be a good UX improvement. :-)

Based on conversations in the farmOS issue queues (see https://github.com/farmOS/farmOS/pull/630#issuecomment-1413844833), I'm going to modify the approach slightly by using a datetime element instead of date and exposing the "time" field with a default value of "midnight". This will make the time available in the action form, but keep the current behavior of defaulting to "midnight". This actually simplifies the code, makes the "midnight" convention more explicit, and has the added benefit of making time configurable.

Automatically closed - issue fixed for 2 weeks with no activity.