package.json: modify the test script to first compile amber_test_runner and then call it

package.json

@@ -23,12 +23,12 @@
         "ambers": "./bin/server"
     },
     "scripts": {
-        "test": "./test/run_build.sh"
+        "test": "./node_modules/grunt/bin/grunt amberc:amber_test_runner; node ./test/amber_test_runner.js"
     },
     "devDependencies": {
-      "pegjs": "~0.7.0",
-      "grunt": "~0.3.17",
-      "grunt-image-embed": "~0.1.3",
-      "grunt-contrib-mincss": "~0.3.2"
+        "pegjs": "~0.7.0",
+        "grunt": "~0.3.17",
+        "grunt-image-embed": "~0.1.3",
+        "grunt-contrib-mincss": "~0.3.2"
     }
 }