Remove gulp-util

[healdev]

gutil.File => https://www.npmjs.com/package/vinyl gutil.replaceExtension => The .extname property on Vinyl objects or https://www.npmjs.com/package/replace-ext gutil.colors => https://www.npmjs.com/package/ansi-colors gutil.date => https://www.npmjs.com/package/date-format gutil.log => https://www.npmjs.com/package/fancy-log gutil.template => https://www.npmjs.com/package/lodash.template gutil.env => https://www.npmjs.com/package/minimist gutil.beep => https://www.npmjs.com/package/beeper gutil.noop => https://www.npmjs.com/package/through2 gutil.isStream => Use the .isStream() method on Vinyl objects gutil.isBuffer => Use the .isBuffer() method on Vinyl objects gutil.isNull => Use the .isNull() method on Vinyl objects gutil.linefeed => Use the string '\n' in your code gutil.combine => https://www.npmjs.com/package/multipipe gutil.buffer => https://www.npmjs.com/package/list-stream gutil.PluginError => https://www.npmjs.com/package/plugin-error