chore(package): write es modules to esm instead of es6 directory

BREAKING CHANGE:

Previously, es modules were published to the es6/ directory inside the npm
package. This change publishes them to the esm directory to be consistent
with other angular packages. Currently, the es6 directory is still published
in the npm package, but will be removed in a future release.

Fixes angular#310

Author: jeffbcross

package.json

@@ -3,12 +3,12 @@
   "version": "2.0.0-beta.2",
   "description": "",
   "main": "./dist/angularfire2.js",
-  "jsnext:main": "./dist/es6/angularfire2.js",
+  "jsnext:main": "./dist/esm/angularfire2.js",
   "scripts": {
     "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 && tsc -p tsconfig.publish.es5.json && tsc -p tsconfig.publish.es6.json",
+    "build_npm": "rm -rf dist && tsc -p tsconfig.publish.es5.json && tsc -p tsconfig.publish.es6.json && tsc -p tsconfig.publish.es6-deprecated.json",
     "postbuild_npm": "cp manual_typings/firebase3/firebase3.d.ts package.json README.md .npmignore dist/ && npm run rewrite_npm_package",
     "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",

tsconfig.publish.es6-deprecated.json

@@ -0,0 +1,19 @@
+{
+  "compilerOptions": {
+    "experimentalDecorators": true,
+    "emitDecoratorMetadata": true,
+    "target": "es6",
+    "noImplicitAny": false,
+    "outDir": "dist/es6",
+    "rootDir": "src",
+    "sourceMap": true,
+    "sourceRoot": "./",
+    "declaration": true,
+    "removeComments": true,
+    "moduleResolution": "node"
+  },
+  "files": [
+    "src/angularfire2.ts",
+    "manual_typings/firebase3/firebase3.d.ts"
+  ]
+}

tsconfig.publish.es6.json

@@ -4,7 +4,7 @@
     "emitDecoratorMetadata": true,
     "target": "es6",
     "noImplicitAny": false,
-    "outDir": "dist/es6",
+    "outDir": "dist/esm",
     "rootDir": "src",
     "sourceMap": true,
     "sourceRoot": "./",