Add a script to enable the usage of CSS3 Media Queries in IE8 and under

This is required since CSS3 Media Queries are not supported in
IE8- ( http://caniuse.com/#feat=css-mediaqueries )

The original script can be found [here](https://github.com/scottjehl/Respond)
Merge pull request #6 from oneclick/ie8-media-queries

Add a script to enable the usage of CSS3 Media Queries in IE8 and under