package.json is missing the version field, which breaks npm install

Request Type: bug

How to reproduce: Try to do:

```
npm install --save-dev https://github.com/angular/angular.js/tarball/master
```

Note that it won't succeed because there's no version in the package.json.

Component(s): misc core

Impact: small

Complexity: small

This issue is related to: 

**Detailed Description:**

This is fixed with pull request https://github.com/angular/angular.js/pull/6752

**Other Comments:**

In order to be able to support `npm install --save-dev https://github.com/angular/angular.js/tarball/master`, repositories need to have a version field in their package.json.