Server tools should display a helpful error message when it fails to
read the server configuration due to insufficient permission

Bug: 1111491
Change-Id: I00baef8967c66946f3c6a166429b5f61cc3e5636
release notes for 0.17.1

Change-Id: If260c6f863486c237499ab53f4c8cd45322bc848
Merge branch 'release-0.17' into develop

Conflicts:
	Server/bkr/server/tools/nag_email.py
Use load_config_or_exit() instead of load_config()

The other server tools were modified as part of fix to BZ#1111491