Added module documentation visualization and fixed haml top bar

Hello,

in order to have a better visualization of the module in the web page I have added the README.md or README.markdown files included in the own compressed module, and parsed to html using redcarpet library (https://github.com/vmg/redcarpet) to be conveniently shown.

I have also fixed some issues with the top bar, which didn't correctly show the title of the modules.

Best regards,
José Molina Colmenero
The documentation goes just after the general data. If #{metadata["documentation"]} is null then no documentation is shown.