Fixes #9 Support for rendering of help information for each panel
 - Added Markdown support on the client side using the library: https://github.com/evilstreak/markdown-js
 - Added new method in the metadataService to retrieve the panels additional information from the external file data.json
 - Replace deprecated ConfigurationHolder with grailsApplication
 - If there is panel info an icon appears in the panel header on the right hand side