remove write to disk/db from receiver config, will always write, introduced kStoreInDatabase ingest mode

Squashed commit of the following:

commit 5383b541ac08e62782769bf82ee19fb128139fb2
Author: Sergey Yakubov <sergey.yakubov@desy.de>
Date:   Tue Jun 30 01:52:41 2020 +0200

    change timeout

commit 3b8be6cd51a3b6ee4aadce144fe47037bd3bcd35
Author: Sergey Yakubov <sergey.yakubov@desy.de>
Date:   Tue Jun 30 00:12:54 2020 +0200

    allow arbitrary group id