[RFC PATCH] gitweb: use HEAD as primary sort key in git_get_heads_list()

Prior to this commit, the "heads" section on a gitweb summary page would list the heads in `-committerdate` order (ie. the most recently-modified ones at the top).

In my own repos I have started to move from "master" towards "main", but I keep "master" around and in sync with "main" so as not to break existing clones. As such, they always point at the same commit.

This means that in the "heads" listing of a gitweb instance, the display order ends up being determined by how `git for-each-ref` decides to tie-break "master" and "main"

For example, right now on a sample repo, gitweb shows the heads in this order, even though "master" and "main" reference the same commit. The tie-breaking evidently isn't happening lexicographically:

- master
- main
- pu
- next

So, this commit adds another `--sort` parameter to the `git for-each-ref` invocation in `git_get_heads_list()`, ensuring that the `HEAD` ref always ends up getting sorted to the top:

- main
- master
- pu
- next

This seems to be a useful change, because I can't see anywhere else in the gitweb UI where we actually indicate to the user what the "default" branch is (ie. what they'll checkout if they run `git clone`).

Signed-off-by: Greg Hurrell <greg@hurrell.net>
---

Resending because I forgot the Signed-off-by the first time. Sorry for the noise.

 gitweb/gitweb.perl | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)