Added 4 features: version, expand all, collapse all and autoload

- Versions now displayed for all submodules
- expand all JSON button
- collapse all JSON button
- Extension is automatically loaded on qualified urls
Update README.md

Added installation instructions.
Update README.md

Adding introduction
Update README.md
Adding "Copy to Clipboard" functionality

- Needed to refactor JS so that the chrome extension API is available
- added jQuery
- added backgorund.js for doing the actual copy-to-clipboard
Merge pull request #2 from jonycheung/master

5 features added: submodule version, expand all, collapse all, copy JSON and autoload