Allow Mahara to record SAML auth attributes to help diagnose auth problems

[Robert Lyon]

So that we can diagnose issues where the attributes being passed in from IdP are not authenticating a user.

In case things like:
- username has changed on IdP end and we still expect old version
- expected attributes, eg email address, are not being sent
- institution name has changed

So we can adjust the Mahara side to expect the new attribute values

[Mahara Bot (dev-mahara)]

Patch for "master" branch: https://reviews.mahara.org/10638

[Mahara Bot (dev-mahara)]

Reviewed: https://reviews.mahara.org/10638
Committed: https://git.mahara.org/mahara/mahara/commit/f27d2d79cdd5102e17f9b41fcc8782fdfb98d75a
Submitter: Cecilia Vela Gurovic (<email address hidden>)
Branch: master

commit f27d2d79cdd5102e17f9b41fcc8782fdfb98d75a
Author: Robert Lyon <email address hidden>
Date: Tue May 7 07:53:01 2019 +1200

Bug 1855327: Adding custom table to record SAML logins attributes

To allow for diagnosing problems with SAML auth connection to IdP

Records what auth attributes the user is trying to authenicate with,
eg institution, email address, username etc.

A config flag is also made to allow one to turn on/of the recording
The data is only stored in the database and is not exposed to the site
itself

behatnotneeded

Change-Id: I5766cf64be048fd1fe0771c9aed3e83e888ff650
Signed-off-by: Robert Lyon <email address hidden>