This adds the option for enabling and disabling anonymous access to a
repo via adding the pseudo-user "daemon" to gitolite's access list.
If anonymous Git access is enabled, GitLab will display the access link
on the repo.
Obviously, your GitD must be configured with the correct base directory
and execute as the appropriate user (probably git).
Previously, I had renamed the update_project_config function in
expectation of future manipulation, but given that Ruby supports using
one argument as the default for another, the current logic can be
disposed of and simplified.