/*
** If g.argv[arg] exists then it is either the name of a repository
** that will be used by a server, or else it is a directory that
** contains multiple repositories that can be served.  If g.argv[arg]
** is a directory, the repositories it contains must be named
** "*.fossil".  If g.argv[arg] does not exist, then we must be within
** an open check-out and the repository to serve is the repository of
** that check-out.
**
** Open the repository to be served if it is known.  If g.argv[arg] is
** a directory full of repositories, then set g.zRepositoryName to
** the name of that directory and the specific repository will be
** opened later by process_one_web_page() based on the content of
** the PATH_INFO variable.