* 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
* style opti
* fix#625
* update changelog
* fix error when selection in not in edit area
* also fix double click front icon and error happen
* fix error when click front icons and toolbars of table
* rebase master
* update some codes
* null check in all selection.getCursorRange method
* add maskColor variable
* update roadmap, remove note features
* feat: open external link and local markdown file
* image view
* browse image by CmdOrCtrl + click
* use esc to close image viewer
* change image viewer z-index to prevent math render show on top of it
* support windows and linux
* feat: basic use of code block by prism
* opti: remove codemirror from muya
* feat: add highlight to math and frontmatter
* feat: import and export in math block, html block, frontmatter, code block
* update: paragraph ctrl
* feat: copy and paste in new math block and html block
* feat: update code block style in dark theme
* feat: search and replace in code block
* fix: update menu item status when selection changed
* opti: optimization of updateCtrl divide it into clickCtrl and inputCtrl
* opti: search and replace in code block when no lang selected
* opti: copy paste in code block
* feat: insert paragraph before or after code block
* opti: change emoji.js to emoji.json
* feat: auto indent in code block
* opti: auto indent in code block
* opti: remove the use of snabbdom-virtualize
* fix: do not show format float box in code block
* opti: emoji picker
* update: delete some unused codes
* update: electron
* use a temp prismjs2 instead of prismjs
