Fix es6 charset detecter
Fix es6 charset detecter

orlando/sprockets,Andreis13/sprockets,masarakki/sprockets,kappezoro/sprockets,bdezonia/sprockets,basecamp/sprockets,recursecenter/sprockets,guilleiguaran/sprockets,maclover7/sprockets,JuanitoFatas/sprockets,jcoyne/sprockets,rails/sprockets,askl56/sprockets,eileencodes/sprockets,prathamesh-sonpatki/sprockets,prusswan/sprockets,sferik/sprockets,jeremy/sprockets,daniel-rikowski/sprockets