Misc minor changes (angular#205)

* refactor(providers): allow offline compilation

* chore(npm): automatically install typings on npm i

Author: vicb

package.json

@@ -8,8 +8,9 @@
     "test": "npm run build; karma start",
     "docs": "typedoc --out docs/api/ --module commonjs --mode modules --name AngularFire2 src",
     "build": "rm -rf dist; tsc",
-    "build_npm": "rm -rf dist && ./node_modules/.bin/tsc -p tsconfig.publish.es5.json && ./node_modules/.bin/tsc -p tsconfig.publish.es6.json",
+    "build_npm": "rm -rf dist && tsc -p tsconfig.publish.es5.json && tsc -p tsconfig.publish.es6.json",
     "postbuild_npm": "cp package.json README.md .npmignore dist/ && npm run rewrite_npm_package",
+    "postinstall": "typings install",
     "rewrite_npm_package": "node --harmony_destructuring tools/rewrite-published-package.js",
     "build_bundle": "cp -r src angularfire2 && tsc typings/main.d.ts angularfire2.ts --rootDir . --module system -t es5 --outFile dist/bundles/angularfire2.js  --moduleResolution node --emitDecoratorMetadata --experimentalDecorators"
   },

src/angularfire2.ts

@@ -38,22 +38,33 @@ function getAbsUrl (root:string, url:string) {
 }
 
 export const COMMON_PROVIDERS: any[] = [
-  provide(FirebaseRef, {
-    useFactory: (url:string) => new Firebase(url),
-    deps: [FirebaseUrl]}),
+  {
+    provide: FirebaseRef,
+    useFactory: _getFirebase,
+    deps: [FirebaseUrl]
+  },
   FirebaseAuth,
   AngularFire,
   FirebaseDatabase
 ];
 
+function _getFirebase(url:string): Firebase {
+  return new Firebase(url);
+}
+
 export const FIREBASE_PROVIDERS:any[] = [
   COMMON_PROVIDERS,
-  provide(AuthBackend, {
-    useFactory: (ref: Firebase) => new FirebaseSdkAuthBackend(ref, false),
+  {
+    provide: AuthBackend,
+    useFactory: _getAuthBackend,
     deps: [FirebaseRef]
-  })
+  }
 ];
 
+function _getAuthBackend(ref: Firebase): FirebaseSdkAuthBackend {
+  return new FirebaseSdkAuthBackend(ref, false);
+}
+
 /**
  * Used to define the default Firebase root location to be
  * used throughout an application.