Merge branch 'jc/a-commands-without-the-repo'

Merge branch 'jc/a-commands-without-the-repo'

Commands that can also work outside Git have learned to take the
repository instance "repo" when we know we are in a repository, and
NULL when we are not, in a parameter.  The uses of the_repository
variable in a few of them have been removed using the new calling
convention.

* jc/a-commands-without-the-repo:
  archive: remove the_repository global variable
  annotate: remove usage of the_repository global
  git: pass in repo to builtin based on setup_git_directory_gently