Merge branch 'mg/gpg-interface-using-status' into maint

Merge branch 'mg/gpg-interface-using-status' into maint

Verification of signed tags were not done correctly when not in C
or en/US locale.

* mg/gpg-interface-using-status:
  pretty: make %GK output the signing key for signed commits
  pretty: parse the gpg status lines rather than the output
  gpg_interface: allow to request status return
  log-tree: rely upon the check in the gpg_interface
  gpg-interface: check good signature in a reliable way