add error handler to chokidar instance (fixes #469)
add error handler to chokidar instance (fixes #469)

oddbird/nunjucks,robgraeber/nunjucks,pardo/nunjucks,pardo/nunjucks,devoidfury/nunjucks,oddbird/nunjucks,mozilla/nunjucks,kevinschaul/nunjucks,kevinschaul/nunjucks,robgraeber/nunjucks,atorkhov/nunjucks,devoidfury/nunjucks,kevinschaul/nunjucks,internalfx/nunjucks,internalfx/nunjucks,oddbird/nunjucks,robgraeber/nunjucks,internalfx/nunjucks,robgraeber/nunjucks,pardo/nunjucks,devoidfury/nunjucks,oddbird/nunjucks,internalfx/nunjucks,mozilla/nunjucks,atorkhov/nunjucks,kevinschaul/nunjucks,atorkhov/nunjucks,atorkhov/nunjucks,mozilla/nunjucks,pardo/nunjucks