Removes Grunt; adds cleancss and uglifyjs3 (#2067)

* Removes grunt, adds cleancss and uglify-js3

Adding package-lock.json

* Forgot load-grunt-tasks

* Forgot to update dist script

Gruntfile.coffee

@@ -1,16 +0,0 @@
-module.exports = (grunt) ->
-    require('load-grunt-tasks') grunt, pattern: ['grunt-contrib-*', 'grunt-sass']
-
-    grunt.initConfig
-
-        uglify:
-          c3:
-            files:
-              'c3.min.js': 'c3.js'
-
-        cssmin:
-          c3:
-            src: 'c3.css'
-            dest: 'c3.min.css'
-
-    grunt.registerTask 'minify', ['cssmin', 'uglify']

package.json

@@ -8,11 +8,14 @@
     "prepublish": "npm run dist",
     "lint": "jshint --reporter=node_modules/jshint-stylish src/ spec/",
     "build": "npm run build:js && npm run build:css",
-    "build:js": "rollup -f umd --name c3 --globals d3:d3 src/index.js > c3.js",
-    "build:css": "node-sass src/scss/main.scss > c3.css",
-    "minify": "grunt minify",
+    "build:js": "npm run build:js:rollup && npm run build:js:uglify",
+    "build:js:rollup": "rollup -f umd --name c3 --globals d3:d3 src/index.js > c3.js",
+    "build:js:uglify": "uglifyjs c3.js --compress --mangle -o c3.min.js",
+    "build:css": "npm run build:css:sass && npm run build:css:min",
+    "build:css:sass": "node-sass src/scss/main.scss > c3.css",
+    "build:css:min": "cleancss -o c3.min.css c3.css",
     "test": "npm run build && npm run lint && karma start karma.conf.js",
-    "dist": "npm run build && npm run minify",
+    "dist": "npm run build",
     "codecov": "cat coverage/*/lcov.info | codecov"
   },
   "repository": {
@@ -32,11 +35,8 @@
     "d3": "~3.5.0"
   },
   "devDependencies": {
+    "clean-css-cli": "^4.1.3",
     "codecov.io": "^0.1.6",
-    "grunt": "^0.4.5",
-    "grunt-cli": "^1.2.0",
-    "grunt-contrib-cssmin": "^0.10.0",
-    "grunt-contrib-uglify": "~0.4.0",
     "jasmine-core": "^2.3.4",
     "jshint": "^2.9.4",
     "jshint-stylish": "^2.1.0",
@@ -45,10 +45,10 @@
     "karma-jasmine": "^0.3.6",
     "karma-phantomjs-launcher": "^0.2.1",
     "karma-spec-reporter": "0.0.20",
-    "load-grunt-tasks": "~0.2.0",
     "node-sass": "^4.5.3",
     "node-static": "^0.7.9",
     "phantomjs": "^1.9.18",
-    "rollup": "^0.41.6"
+    "rollup": "^0.41.6",
+    "uglify-js": "^3.0.15"
   }
 }