Include dotfiles when copying template directory, which will handle
both a template directory itself that begins with a dotfile, and
any dotfiles inside the directory.

These are not quite like their plain counterparts and require special handling.

cc @carlosmn

This is where portable git stores the global configuration which we can
use to adhere to it even though git isn't quite installed on the system.

Win32 Reserved names: don't reserve names outside the working directory

Check that the repository directory is beneath the workdir before
adding it to the list of reserved paths.  If it is not, then there
is no possibility of checking out files into it, and it should not
be a reserved word.

This is a particular problem with submodules where the repo directory
may be in the super's .git directory.

Untangle git_futils_mkdir from git_futils_mkdir_ext - the latter
assumes that we own everything beneath the base, as if it were
being called with a base of the repository or working directory,
and is tailored towards checkout and ensuring that there is no
bogosity beneath the base that must be cleaned up.

This is (at best) slow and (at worst) unsafe in the larger context
of a filesystem where we do not own things and cannot do things like
unlink symlinks that are in our way.

Remove run-time configuration settings from submodules