Add .gitbugtraq to initial commit in new repo

When creating a new repository, a checkbox to allow the addition of a
.gitbugtraq file to the initial commit is visible if the server contains
a non-empty file named ${baseFolder}/gitbugtraq.  If a new repository is
created with this checkbox checked, the contents of this server file are
used to populate .gitbugtraq in the new repository's initial commit.