Is there interest in reading ~/.gitconfig.d/* and /etc/gitconfig.d/*?

["Ævar Arnfjörð Bjarmason" <avarab@gmail.com>]

I've patched Git to read ~/.gitconfig.d/* and /etc/gitconfig.d/* in
addition to reading ~/.gitconfig and /etc/gitconfig where it would
normally do so. the gitconfig.d/* files are read in numeric sort order
as is the custom with such files and read after the main .gitconfig
file so they override it.

This is very useful for me because I maintain my .gitconfig in a
public git repository but I don't want anyone to know my github.token.
Because of that I have to do a little song & dance every time I commit
to the file (if the token is part of the diff) or pull to the file (to
not encounter a merge conflict).

This would also facilitate neat stuff like easily using bits of other
people's gitconfig libraries by cloning their repository somewhere and
symlinking their .gitconfig to ~/.gitconfig.d/99-some-library.

I'm not attaching my patch because it would be inhumane to subject
anyone to it in its current state. However, I'd like to ask if there's
any interest in getting a proper & documented patch for this. If so I
can submit a proper patch, if not I can just continue to patch my Git
build with my hack.

Apologies if this has been brought up before. I tried to search for
prior art but ".gitconfig.d" makes for a really bad search query in
all the search engines I could find that index this list.