Simplify build scripts to use npm instead of gulp

- Close #229

package.json

@@ -1,33 +1,42 @@
 {
-  "name": "minimal-mistakes-jekyll-theme",
-  "version": "2.0.0",
+  "name": "minimal-mistakes",
+  "version": "2.1.0",
+  "description": "Minimal Mistakes Jekyll theme npm build scripts",
   "repository": {
     "type": "git",
     "url": "git://github.com/mmistakes/minimal-mistakes.git"
   },
   "keywords": [
     "jekyll",
-    "gulp"
+    "theme",
+    "minimal"
   ],
   "author": "Michael Rose",
   "license": "MIT",
   "bugs": {
     "url": "https://github.com/mmistakes/minimal-mistakes/issues"
   },
-  "homepage": "https://github.com/mmistakes/minimal-mistakes",
-  "devDependencies": {
-    "gulp": "^3.9.1",
-    "gulp-autoprefixer": "^3.1.0",
-    "gulp-imagemin": "^2.4.0",
-    "gulp-jshint": "^2.0.0",
-    "gulp-plumber": "^1.1.0",
-    "gulp-rename": "^1.2.2",
-    "gulp-sass": "^2.2.0",
-    "gulp-uglify": "^1.5.3",
-    "gulp-uglifyjs": "^0.6.2",
-    "jshint": "^2.9.1"
+  "homepage": "https://mmistakes.github.io/minimal-mistakes/",
+  "engines": {
+    "node": ">= 0.10.0"
   },
-  "dependencies": {
-    "imagemin-mozjpeg": "^5.1.0"
+  "devDependencies": {
+    "autoprefixer": "^6.3.5",
+    "node-sass": "^3.4.2",
+    "npm-run-all": "^1.7.0",
+    "onchange": "^2.2.0",
+    "postcss-cli": "^2.5.1",
+    "uglify-js": "^2.6.1"
+  },
+  "scripts": {
+    "scss": "node-sass --output-style compressed -o assets/css assets/_scss",
+    "autoprefixer": "postcss -u autoprefixer -b \">, 5%, ie 9\" -r assets/css/*",
+    "uglify": "uglifyjs assets/js/vendor/jquery/jquery-1.12.1.min.js assets/js/plugins/jquery.fitvids.js assets/js/plugins/jquery.greedy-navigation.js assets/js/plugins/jquery.magnific-popup.js assets/js/plugins/jquery.smooth-scroll.min.js assets/js/plugins/stickyfill.min.js assets/js/_main.js -c -m -o assets/js/main.min.js",
+    "watch:css": "onchange \"assets/_scss/**/*.scss\" -- npm run build:css",
+    "watch:js": "onchange \"assets/js/**/*.js\" -e \"assets/js/main.min.js\" -- npm run build:js",
+    "watch:all": "npm-run-all --parallel watch:css watch:js",
+    "build:css": "npm run scss && npm run autoprefixer",
+    "build:js": "npm run uglify",
+    "build:all": "npm run build:css && build:js"
   }
 }