Merge branch 'jt/repo-stats' into jch

"git repo stats", a new command.

Comments?

* jt/repo-stats:
  builtin/repo: add progress meter for stats
  builtin/repo: add keyvalue and nul format for stats
  builtin/repo: add object counts in stats output
  builtin/repo: introduce stats subcommand
  ref-filter: allow NULL filter pattern
  builtin/repo: rename repo_info() to cmd_repo_info()

diff --cc t/meson.build
Simple merge