Merge branch 'jk/autoident-test'

Fix test breakages by a builder who does not have a valid user name
in his /etc/password entry.

* jk/autoident-test:
  t7502: test early quit from commit with bad ident
  t7502: handle systems where auto-identity is broken
  t7502: drop confusing test_might_fail call
  t7502: narrow checks for author/committer name in template
  t7502: properly quote GIT_EDITOR
  t7502: clean up fake_editor tests