add get_host_credential_filenames() and fix /etc/grid-security/certificates/ path
add get_host_credential_filenames() and fix
/etc/grid-security/certificates/ path

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