SAML attribute mapping needed

[Robert Lyon]

With SAML now being a plugin within Mhara core we are able to connect easier to external IdPs.

But one problem that remains is understanding payload packets returned.
Some IdP's return the packet of information with human readable keys like 'surname', 'mail' etc
but others return it with oid numbers (including custom oid numbers) and so we need to be able to translate that to human readable text.

We can do this by setting the attribute mapping in our auth/saml/config.php file in the 'authproc.idp' and 'authproc.sp' arrays to use an in built attributemap found in auth/saml/extlib/simplesamlphp/attributemap/ directory.

But the problem (and therefore the reason for this bug) comes when we want to have a custom attributemap. We can't simply add it to auth/saml/extlib/simplesamlphp/attributemap/ as that does not exist in codebase (only created via make ssphp) so we need a way to get our custom attribute mappings into play.

[Mahara Bot (dev-mahara)]

Patch for "master" branch: https://reviews.mahara.org/7925

[Mahara Bot (dev-mahara)]

Reviewed: https://reviews.mahara.org/7925
Committed: https://git.mahara.org/mahara/mahara/commit/bb7c7561696aab4cef3da5eb37d56fcaa2fb5f58
Submitter: Robert Lyon (<email address hidden>)
Branch: master

commit bb7c7561696aab4cef3da5eb37d56fcaa2fb5f58
Author: Cecilia Vela Gurovic <email address hidden>
Date: Mon Aug 14 09:05:31 2017 +1200

Bug 1710005: Custom file mapping for sp and ids in saml

The way it worked before, to add a mapping file we
have to edit the saml config.php code

With this patch, to add a mapping file we can set the variable
saml_custommappingfile with the path to the file
in the mahara config.php file

behatnotneeded
Change-Id: I6396930da8dfdbe1904e469f309cdb4e38d46757