Merge branch 'nr/git-cd-to-a-directory'

Merge branch 'nr/git-cd-to-a-directory'

Just like "make -C <directory>", make "git -C <directory> ..." to
go there before doing anything else.

* nr/git-cd-to-a-directory:
  t0056: "git -C" test updates
  git: run in a directory given with -C option