Add documentation to sp-remote for signature.certificate

Stop calling SimpleSAML_Session::getAttributes() in SimpleSAML_Error_Error class. Use an alternate way to try to fetch user's mail.

Remove error handling code when session fails to initialise in SimpleSAML_Session::getSessionFromRequest().

Remove DATA_TIMEOUT_LOGOUT and expireDataLogout() from SimpleSAML_Session. Now, if we want to store data in the session that needs to go away when logging out, we should do that manually on every logout.

Manually remove logout callbacks data from the session on the SP (instead of using SimpleSAML_Session::DATA_TIMEOUT_LOGOUT).

# By Jakob Schlyter
# Via Jaime Pérez Crespo (1) and Jakob Schlyter (1)
* 'master' of github.com:simplesamlphp/simplesamlphp:
  create /var/lib/simplesamlphp/cert
  bump release
  update vendor
  do not depend on php-pecl-krb5, only used for negotiate
  speling
  typo
  RPM specfile for simpleSAMLphp, tested on CentOS 7

Manually remove idp-ssotime data from the session on the IdP, per association (instead of using SimpleSAML_Session::DATA_TIMEOUT_LOGOUT).

RPM specfile for simpleSAMLphp, tested on CentOS 7

Add $authority parameter to initLogoutReturn which was previously removed instead of making it mandatory.