Robust options to control initial scroll

Originally reported on Google Code with ID 768

Usability issue in all browsers.

When you go to prev/next month/day in the week/day views, it pops back to the hour
as specified in the firstHour option regardless of where you scrolled to on the previous
date range. I think this is a little too presumptuous.  In my case, I want it to retain
the current scrollTop when navigating date ranges.  Other people might want to mimick
Google Calendar and scroll so that the current time is in view.

The issues is caused by the logic in resetScroll function.

I vote for creating an option called autoScroll with the following values:
- first - the first hour of the day which would be the default to maintain backwards
compatability
- current - will scroll to the current time of day like Google Calendar
- remember - will remember where you scrolled to in the previous date range
- none - will do no scrolling logic

Reported by [e-mail] on 2010-12-22 13:07:25

Imported with 4 stars.

[lucianholt97]

Are there any updates on this? @arshaw can you please merge #6178? I tested it locally and it works like expected.
In addition to this, it also fixes the issue that the calendar jumps to the first time when an event is updated. In my case (using an event tooltip with popper) this also destroys the DOM Element of the event and leaves popper confused without any target element.

[arshaw]

as @ParanormalCoder brings up, would be nice to be able to NOT change scroll when going prev/next