Comment 1 for bug 810302

I have pushed a series of commits to gerrit on master (auth_saml_enhancements) that represent the sum total of the changes required for the enhancements sponsored by the Ministry of NZ.
The main features of these changes are to allow users to have dual login mechanisms eg: internal and auth/saml, and then given this, when they login using auth/saml and no link is detected for a Mahara account, they are able to login manually and nominate an account to link to the external authorisation source.

Due to issues with the PHP shutdown callbacks that SimpleSAMLphp registers, it is imperative that people using auth/saml use a separate session storage engine for SimpleSAMLphp other than phpsession - checks have been implemented to guard against this.