Start document at the recent cursor position

[alihardan]

After a document gets loaded, position the cursor on the recent cursor position.

It's necessary for long documents.

[JohnVeness]

For those of us who have "Open preview when opening documents" ticked, I'd like to see similar happen for that view too, where it remembers the last scroll position.

[gsantner]

For anybody - feel free to send a PR for this ;)

[gsantner]

should be done together with #149 .

[gsantner]

I have done this now - position is remembered and restored where possible. This is disabled for special documents (so ToDo and QuickNote still always starts at bottom 😋 ).