Add "main" property to bower.json

Without the `main` property, Grunt will not automatically include the library when building with `grunt server` or `grunt build`.
Merge pull request #43 from skinnyfit/patch-1

Add "main" property to bower.json
Set default protocol to HTTPS for loading Google Chart API

That allow the library to be loaded from PhoneGap that is loaded from the file:// protocol.

Fix #23
Missing semicolon in protocol
Add other Plunkr samples
Add other samples
Add simpler samples and reoganize sample page