Update database.rst

I got very confused following these directions until I figured out that the URL expected me to include 'http://', so I thought it would be helpful to note that in the documentation.
Handle permissions on private mailing-lists
Deal with a disabled search engine
modifications et adaptations aux plugins
Fix unit tests after commit 85423f0
Merge pull request #8 from mairin/patch-1

Update database.rst
Merge https://github.com/hyperkitty/hyperkitty into plugin-api

Conflicts:
	hyperkitty/lib/mailman.py
	hyperkitty/views/list.py
	hyperkitty/views/message.py
	hyperkitty/views/thread.py
No trace of hyperkitty.cfg
reading the archiver gave me correct value
Merge branch 'docfix' into plugin-api