GitBlit integration into Gerrit as repo viewer.

GitBlit is plugged into the Gerrit Servlet Container with
integration of Gerrit authentication, authorisation and
Git repositories.

[gitweb]
        type = custom
        url = plugins/gitblit-plugin-1.0-SNAPSHOT/
        linkname = GitBlit
        project = summary/${project}
        revision = commit/${project}/${commit}
        branch = log/${project}/${branch}
        filehistory = history/${project}/${branch}/${file}

Change-Id: Ie82658bcbbf308520d48b88057212a683aca16a7