Bug 31378: Add domain settings to IdP add page

Bug 31378: Add domain settings to IdP add page

This patch introduces a small form for an initial domain configuration
to the 'New identity provider' page, to avoid confusion on testers about
required settings for things to work.

To test:
1. Apply this patch
2. Verify you are now offered a configuration section for domain
   settings. Fields like 'Default category' and 'Default library' are
   mandatory.
3. Choosing some values makes them get stored on 'Submit'

Signed-off-by: Tomas Cohen Arazi <tomascohen@theke.io>
Signed-off-by: Martin Renvoize <martin.renvoize@ptfs-europe.com>
Signed-off-by: Tomas Cohen Arazi <tomascohen@theke.io>