- add myproxy_creds_verify_passphrase() to have passphrase logic in   one place. we verify the passphrase by either trying to decrypt the   key (new method) or comparing with the stashed crypted passphrase   (for backward compat) - don't write out crypted passphrase anymore. we can check the   passphrase by trying to decrypt the private key (new method)
- add myproxy_creds_verify_passphrase() to have passphrase logic in
  one place. we verify the passphrase by either trying to decrypt the
  key (new method) or comparing with the stashed crypted passphrase
  (for backward compat)
- don't write out crypted passphrase anymore. we can check the
  passphrase by trying to decrypt the private key (new method)

ellert/globus-toolkit,gridcf/gct,globus/globus-toolkit,gridcf/gct,ellert/globus-toolkit,gridcf/gct,globus/globus-toolkit,ellert/globus-toolkit,gridcf/gct,globus/globus-toolkit,globus/globus-toolkit,ellert/globus-toolkit,ellert/globus-toolkit,globus/globus-toolkit,globus/globus-toolkit,ellert/globus-toolkit,ellert/globus-toolkit,gridcf/gct,gridcf/gct,globus/globus-toolkit,globus/globus-toolkit,ellert/globus-toolkit