Add license into the webapp instead of linking to Github

[neelabhg]

Clicking on the copyright info in the footer currently opens the LICENSE file on GitHub in a new tab.

This could be modified to fetch the file and show it in a modal popup (similar to how Code Moo does it).

There are many advantages:

• The user stays in the application (and the same tab), instead of being sent to GitHub, leading to a better user experience
• The LICENSE file will be served from GitHub Pages instead of github.com:
  • GitHub Pages uses a CDN, so the file will be accessed faster and more efficiently
  • Opening github.com will unnecessarily download accompanying HTML, CSS and JS
• The LICENSE file will be bundled with the application (so changes to the license do not affect the license used by the deployed application)