Add experimental spellcheck option
Add experimental spellcheck option

Closes #4113

nightwing/CodeMirror,nightwing/CodeMirror,wingify/CodeMirror,ficristo/CodeMirror,pabloferz/CodeMirror,namin/CodeMirror,notepadqq/CodeMirror,xeronith/CodeMirror,adobe/CodeMirror2,crazy4chrissi/CodeMirror,jayaprabhakar/CodeMirror,ficristo/CodeMirror,namin/CodeMirror,thomasjm/CodeMirror,wingify/CodeMirror,MarcelGerber/CodeMirror,mtaran-google/CodeMirror,jkaplon/CodeMirror,crazy4chrissi/CodeMirror,jkaplon/CodeMirror,xeronith/CodeMirror,TDaglis/CodeMirror,schanzer/CodeMirror,ejgallego/CodeMirror,INTELOGIE/CodeMirror,ejgallego/CodeMirror,ejgallego/CodeMirror,MarcelGerber/CodeMirror,mtaran-google/CodeMirror,xeronith/CodeMirror,rrandom/CodeMirror,adobe/CodeMirror2,dperetti/CodeMirror,nightwing/CodeMirror,ficristo/CodeMirror,kerabromsmu/CodeMirror,jkaplon/CodeMirror,rrandom/CodeMirror,alur/CodeMirror,SidPresse/CodeMirror,thomasjm/CodeMirror,grzegorzmazur/CodeMirror,schanzer/CodeMirror,sourcelair/CodeMirror,SidPresse/CodeMirror,dperetti/CodeMirror,wingify/CodeMirror,INTELOGIE/CodeMirror,TDaglis/CodeMirror,codio/CodeMirror,sourcelair/CodeMirror,MarcelGerber/CodeMirror,rrandom/CodeMirror,INTELOGIE/CodeMirror,SidPresse/CodeMirror,grzegorzmazur/CodeMirror,schanzer/CodeMirror,alur/CodeMirror,crazy4chrissi/CodeMirror,notepadqq/CodeMirror,kerabromsmu/CodeMirror,hackmdio/CodeMirror,TDaglis/CodeMirror,jayaprabhakar/CodeMirror,grzegorzmazur/CodeMirror,thomasjm/CodeMirror,kerabromsmu/CodeMirror,alur/CodeMirror,mtaran-google/CodeMirror,notepadqq/CodeMirror,jayaprabhakar/CodeMirror,namin/CodeMirror,codio/CodeMirror,sourcelair/CodeMirror,pabloferz/CodeMirror,pabloferz/CodeMirror,codio/CodeMirror,hackmdio/CodeMirror,hackmdio/CodeMirror,adobe/CodeMirror2,dperetti/CodeMirror