Implement WAYF UI with integration of one or more Directory Services, following the current Nextcloud developments

[mickenordin]

[MahdiBaghbani]

I've added functionality to oCIS UI to accept the invite tokens from URL, like this:

https://3.ocis.cloud.test.azadehafzar.io/open-cloud-mesh/accept-invite?token=989fghfg5-57cc-4a1e-b74c-247b80f76d8e&providerDomain=sunet-eosc.drive.test.sunet.se

[MahdiBaghbani]

My PRs for this task

Reva (multiverse)

Main (CERNBox): cs3org/reva#5385
oCIS: owncloud/reva#432
OpenCloud: opencloud-eu/reva#393

Enterprise File Sync and Share Softwares

oCIS: owncloud/ocis#11758
OpenCloud: opencloud-eu/opencloud#1714

Graphical User Interfaces:

CERNBox:
oCIS: owncloud/web#13243
OpenCloud: opencloud-eu/web#1486
Nextcloud: