New service: storage-kiteworks

[mmattel]

References : owncloud/ocis#12300 (feat(kiteworks): add Kiteworks storage provider service)

[DeepDiver1975]

not really - this all is early POC. Unclear if ever officially released .... I see no reason to invest into documentation at this point in time
@kobergj you call - I'd close this

[mmattel]

Note, this issue is a reminder.
I do this for all potential doc changes.

It will be closed when the referenced PR gets closed.
But if it is merged, I can find it easily to add the relevant docs for.