Merge pull request #650 from HackerWins/develop

v0.5.10
Add TWBS3 responsive col-* for help dialog
Restore prev/next functions in core/list.js
add simple plugin system
add simple plugin system
Added shortcuts setting that will be either true or false
Only enable shortcuts if the option is set to true
added dist files
Added onsubmit callback
Update summernote-tr-TR.js
Merge pull request #671 from eka7a/develop

Update summernote-tr-TR.js
Embed youtube with wmode as  to prevent showing toolbar dialogs beneath videos
Merge branch 'develop' of github.com:easylogic/summernote into easylogic-develop

Conflicts:
	dist/summernote.js
	dist/summernote.min.js
Merge branch 'easylogic-develop' into develop
Merge branch 'develop' into youtube-as-opaque

Conflicts:
	dist/summernote.js
Merge pull request #678 from HackerWins/youtube-as-opaque

Embed youtube with wmode as opaque
Redesign plugin interface with editor and renderer and language and so on.
 - Extract video plugin from base code
Merge branch 'develop' into feature/extract-video-plugin

Conflicts:
	dist/summernote.js
	dist/summernote.min.js
	src/js/editing/Editor.js
Update README.md
Added missing typos (subscript/superscript) in ko-KR Locale.