Update example cgtirc settings
    
    Add a number of settings from the example cgitrc file section of the
    documentation.  Update the config to reflect the default values, leaving
    them commented.
    
    Several settings which previously overrode the cgit defaults no longer
    do so.  Those settings are: enable-commit-graph, enable-index-links,
    enable-log-filecount, enable-log-linecount, and max-stats.