build: Switch to eslint

Closes #42.

.eslintrc.json

@@ -0,0 +1,6 @@
+{
+	"extends": "wikimedia",
+	"env": {
+		"node": true
+	}
+}

Gruntfile.js

@@ -1,33 +1,26 @@
 module.exports = function ( grunt ) {
-	grunt.loadNpmTasks( 'grunt-contrib-jshint' );
 	grunt.loadNpmTasks( 'grunt-contrib-watch' );
-	grunt.loadNpmTasks( 'grunt-jscs' );
+	grunt.loadNpmTasks( 'grunt-eslint' );
 	grunt.loadNpmTasks( 'grunt-jsonlint' );
 	grunt.loadTasks( 'build/tasks' );
 
 	grunt.initConfig( {
-		jshint: {
-			options: {
-				jshintrc: true
-			},
+		eslint: {
 			all: [ '*.js', '{build,src,test}/**/*.js' ]
 		},
-		jscs: {
-			all: '<%= jshint.all %>'
-		},
 		jsonlint: {
 			all: 'test/data.json'
 		},
 		watch: {
 			files: [
-				'.{jscsrc,jshintignore,jshintrc}',
-				'<%= jshint.all %>',
+				'.eslintrc.json',
+				'<%= eslint.all %>',
 				'test/data.json'
 			],
 			tasks: [ 'test' ]
 		}
 	} );
 
-	grunt.registerTask( 'test', [ 'jshint', 'jscs', 'jsonlint', 'unit' ] );
+	grunt.registerTask( 'test', [ 'eslint', 'jsonlint', 'unit' ] );
 	grunt.registerTask( 'default', 'test' );
 };

build/tasks/unit.js

@@ -1,3 +1,5 @@
+/* eslint-disable no-console */
+
 module.exports = function ( grunt ) {
 	grunt.registerTask( 'unit', function () {
 		var assert = require( 'assert' ),

package.json

@@ -21,11 +21,10 @@
   },
   "dependencies": {},
   "devDependencies": {
-    "grunt": "0.4.5",
-    "grunt-cli": "0.1.13",
-    "grunt-contrib-jshint": "1.0.0",
-    "grunt-contrib-watch": "0.6.1",
-    "grunt-jscs": "2.7.0",
-    "grunt-jsonlint": "1.0.4"
+    "eslint-config-wikimedia": "0.3.0",
+    "grunt": "1.0.1",
+    "grunt-contrib-watch": "1.0.0",
+    "grunt-eslint": "18.0.0",
+    "grunt-jsonlint": "1.0.8"
   }
 }

src/cssjanus.js

@@ -259,6 +259,8 @@ function CSSJanus() {
 	/**
 	 * @private
 	 * @param {string} match
+	 * @param {string} property
+	 * @param {string} offset
 	 * @return {string}
 	 */
 	function calculateNewShadow( match, property, offset ) {
@@ -268,6 +270,10 @@ function CSSJanus() {
 	/**
 	 * @private
 	 * @param {string} match
+	 * @param {string} property
+	 * @param {string} color
+	 * @param {string} space
+	 * @param {string} offset
 	 * @return {string}
 	 */
 	function calculateNewFourTextShadow( match, property, color, space, offset ) {