Use coffeescript again for Gulp

gulpfile.js

@@ -1,64 +0,0 @@
-'use strict';
-
-global.gulp = require('gulp');
-global.plugins = require('gulp-load-plugins')();
-
-global.config = {
-    autoprefixer: {
-        browsers: 'last 2 versions'
-    },
-    bowerDir: 'vendor/bower',
-    fonts: {
-        outputDir: 'source/assets/fonts'
-    },
-    htmlmin: {
-        collapseWhitespace: true
-    },
-    js: {
-        sourceDir: 'assets/js',
-        pattern: '/js/**/*.js',
-        outputDir: 'source/assets/js'
-    },
-    production: plugins.util.env.production || false,
-    sass: {
-        sourceDir: 'assets/sass',
-        pattern: '/**/*.sass',
-        outputDir: 'source/assets/css'
-    },
-    scss: {
-        pattern: '/**/*.scss'
-    }
-}
-
-global.app = {};
-
-app.sass = function (paths, filename) {
-    gulp.src(paths)
-        .pipe(plugins.plumber())
-        .pipe(plugins.if(!config.production, plugins.sourcemaps.init()))
-        .pipe(plugins.sassGlob())
-        .pipe(plugins.sass())
-        .pipe(plugins.autoprefixer(config.autoprefixer))
-        .pipe(plugins.concat(filename))
-        .pipe(plugins.if(config.production, plugins.cleanCss()))
-        .pipe(plugins.if(!config.production, plugins.sourcemaps.write('.')))
-        .pipe(plugins.if(!config.production, plugins.refresh()))
-        .pipe(gulp.dest(config.sass.outputDir));
-};
-
-app.js = function (paths, filename) {
-    gulp.src(paths)
-        .pipe(plugins.plumber())
-        .pipe(plugins.if(!config.production, plugins.sourcemaps.init()))
-        .pipe(plugins.concat(filename))
-        .pipe(plugins.if(config.production, plugins.uglify()))
-        .pipe(plugins.if(!config.production, plugins.sourcemaps.write('.')))
-        .pipe(gulp.dest(config.js.outputDir));
-};
-
-app.copy = function (source, destination) {
-    gulp.src(source)
-        .pipe(gulp.dest(destination));
-};
-
-require('require-dir')('./gulp');