added docs for new rubocop option
added docs for new rubocop option

Glavin001/atom-beautify,janmolnar/atom-beautify,janmolnar/atom-beautify,prettydiff/atom-beautify,dvingo/atom-beautify,Glavin001/atom-beautify,Glavin001/atom-beautify,janmolnar/atom-beautify,prettydiff/atom-beautify,Glavin001/atom-beautify,prettydiff/atom-beautify,janmolnar/atom-beautify,janmolnar/atom-beautify,janmolnar/atom-beautify,janmolnar/atom-beautify,janmolnar/atom-beautify,dvingo/atom-beautify,dvingo/atom-beautify,prettydiff/atom-beautify,Glavin001/atom-beautify,janmolnar/atom-beautify,dvingo/atom-beautify,janmolnar/atom-beautify,janmolnar/atom-beautify,dvingo/atom-beautify,janmolnar/atom-beautify,janmolnar/atom-beautify,janmolnar/atom-beautify