Adding support for self registration to Virtual Organisations

Adds support for creating and managing virtual organisations which use PIN protection to allow members to self register to join.

implements: bp vo-management

Change-Id: I80196391ec56bffb0c4b69da2cf9706c8ec85c58
Co-Authored-By: Kristy Siu <kwss@kent.ac.uk>
Co-Authored-By: David Chadwick <d.w.chadwick@kent.ac.uk>
Add ``user`` object to the mapping rules examples.

Every rule should have a local ``user`` object that is used to
produce a unique user_id of the federated user. Not all examples of the
OS-FEDERATION extension included such object.

Change-Id: Ib1a2a956cb3638402b283ad13841f48d31814240
Closes-Bug: #1312221
Revert "Trusted Attributes Policy for External Identity Providers"

This reverts commit d82be8f5637960295f5190adb286f0c62d176e9b.

Change-Id: I505373ce762314834991ac7329e8620a84ffe91f
Fix links sections in federation mapping docs

Links sections are misplaced in some OS-FEDERATION mappings'
API HTTP request/response examples. They need to be moved to appropriate
objects.

Closes-Bug: #1336258
Change-Id: I076b3fcfa3067b37b30280e9d00481b5a4eda671
Updated from global requirements

Change-Id: Ib32ce53ebb620f1896910bc373da4f907806532d
Updates pom and fixes a problem to fix the build

Change-Id: I58b48355334ec058c4fbbf1ee56867328e7bb227
Merge "Revert "Trusted Attributes Policy for External Identity Providers""
Merge "Fix links sections in federation mapping docs"
Remove duplicate section title

Two sections were entitled 'Validate token', whereas the second should
have distinguished itself from the first. Also added a line break after
"New in version..." to show that the entire section is new, not just the
one paragraph.

Change-Id: If6dd9c099950d24f65e861b28f7fc80810c78225
Merge "Updated from global requirements"
Merge "Remove duplicate section title"
Merge "Add ``user`` object to the mapping rules examples."
Merge "Adding support for self registration to Virtual Organisations"
Revert "Adding support for self registration to Virtual Organisations"

I don't think this should be approved and merged.

This reverts commit f2be051111278f0d2bdb77cc43e9f658eb7da1ed.

Change-Id: I8ff63be73e083064914c5b54dbf646944fd038d4
Merge "Revert "Adding support for self registration to Virtual Organisations""