Allow running the tests with npm test

Also, make sure `npm install` installs the test dependencies.

package.json

@@ -1,31 +1,38 @@
-{
-  "name": "css-parser",
-  "version": "0.1.0",
-  "description": "Standards-based CSS parser, based on the CSS Syntax spec.",
-  "keywords": ["css", "parser"],
-  "author": "Tab Atkins <[email protected]>",
-  "repository": {
-    "type": "git",
-    "url": "git://github.com/tabatkins/css-parser.git"
-  },
-  "main": "index",
-  "homepage": "https://github.com/tabatkins/css-parser",
-  "contributors": [
-    {
-      "name": "Tab Atkins Jr."
-    }
-  ],
-  "bugs": {
-    "url": "https://github.com/tabatkins/css-parser/issues",
-    "email": "[email protected]"
-  },
-  "dependencies": {},
-  "devDependencies": {},
-  "licenses": [
-    {
-      "type": "CC0",
-      "url": "http://github.com/tabatkins/css-parser/raw/master/LICENSE"
-    }
-  ],
-  "scripts": {}
-}
+{
+  "name": "parse-css",
+  "version": "0.1.0",
+  "description": "Standards-based CSS parser, based on the CSS Syntax spec.",
+  "keywords": [
+    "css",
+    "parser"
+  ],
+  "author": "Tab Atkins <[email protected]>",
+  "repository": {
+    "type": "git",
+    "url": "git://github.com/tabatkins/parse-css.git"
+  },
+  "main": "index",
+  "homepage": "https://github.com/tabatkins/parse-css",
+  "contributors": [
+    {
+      "name": "Tab Atkins Jr."
+    }
+  ],
+  "bugs": {
+    "url": "https://github.com/tabatkins/parse-css/issues",
+    "email": "[email protected]"
+  },
+  "dependencies": {},
+  "devDependencies": {
+    "ansidiff": "^1.0.0"
+  },
+  "licenses": [
+    {
+      "type": "CC0",
+      "url": "http://github.com/tabatkins/parse-css/raw/master/LICENSE"
+    }
+  ],
+  "scripts": {
+    "test": "node tests.js"
+  }
+}