Feature: Improvements of formatting in preview mode on web & Android

[ghost]

To improve the presentation of the note content in preview mode:

Web + Android:

1. Increase line spacing between list items
2. Create additional format of intended bullets (I suggest the standard hollow bullet, square, then ordinary bullet again)

Android

1. Increase space between titles and other elements (this is done on the web interface but not Android)
2. Decrease size of titles -- the difference between titles and text is too big.

A good example of formatting is Typora.

Thank you! Andreas

[tasn]

Looks good, and I guess would be great to have, thanks for opening this ticket!