* support ruby and better raw html display
* finish ruby render
* add kbd style
* if content is empty string, do not hide tag
* update changelog
* add auto complement to inline html
* opti slit words
* opti tool bar style
* support open inline a tag if it is a external link
* fix: auto complete
* add attribute white list
* add comment
* delete some commented codes
* 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