Some cleanup done.
Added emas_DSN to zope environment vars. We will use it in our db
connection in emas.app.memberservice
Move back to simple filestorage instead of zeo.
Remove unused parts.
Use 'head' rather than 'instance' as it protects us from whatever
happends in base.cfg
Merge branch 'memberservice-migration' into performance-tuning

Conflicts:
	production.cfg
	qa.cfg