Ref #18: Updated the parameter references and CSS to adjust appearance and theme.
Ref #18: Updated code blocks in Getting Started Guide for syntax highlighting.
Ref #18: Updated the Admin Guide code blocks for syntax highlighting.
Ref #18 Updating Troubleshooting and Reference for code block syntax highlighting.
Merge branch '3.x' of https://github.com/codership/galera into 3.x

Merged documentation updates with Galera.