Reason: if the base url is /wiki, and you are browsing /wiki, then wikilinks that are relative URLS will not work correctly. For example, "Help" will take you to /Help rather than /wiki/Help. The simple solution is to ensure that users are always at /wiki/ rather than /wiki. This has no effect when gitit is being served at the root url. Thanks to MightyByte for pointing out the problem.
Front Page and Help are now initialized correctly depending on the default page type. data/markup.FORMAT files include the markup format-specific parts of the Help page; they are grafted on to the rest by the initialization routine.