* feat: add front menu

* update changelog

* feat: add short cut of paragraph edit

* fix location bug of submenu

* update checkbox style in editor

* update selected background color

* update KEYBINDINGS.md

* Bullet to ordered list issue:

* emit change event after control paragraph

* fix: marked parse error

* disable table, front-matter and horizontal line in paragraph turn into, and fixed paragraph turn into html and math

* fix unwanted space before text paragraph when heading turn into text paragraph

* fix error when turn heading to paragraph

* put front menu on the left on front icon

* update readme

* if the selection span in two lnes, disable paragraph turn into heading