Better default values

For an input like : 

```
[?] Module Name: node
[?] Description: The best module ever.
[?] Homepage: 
[?] License: MIT
[?] GitHub username: 
[?] Author's Name: 
[?] Author's Email: 
[?] Author's Homepage: 
```

The `package.json` would look like : 

```
{
  "name": "node",
  "version": "0.0.0",
  "main": "lib/node.js",
  "description": "The best module ever.",
  "homepage": "https://github.com//node",
  "bugs": "https://github.com//node/issues",
  "author": {
    "name": "",
    "email": ""
  },
  "repository": {
    "type": "git",
    "url": "https://github.com//node"
  },
  "licenses": [
    {
      "type": "MIT"
    }
  ],
  "devDependencies": {
    "grunt-contrib-jshint": "~0.6.0",
    "grunt-contrib-nodeunit": "~0.2.0",
    "grunt-contrib-watch": "~0.5.0"
  }
}
```

Have modified the `index` to set default as blank.