Move initialization of service attributes to function
Group settings and add adapter settings
Use absolute path to service configuration file
Add skeleton for demo adapter and logic for setting up the adapter
Setup database connection in adapter and store adapter instance in session
Use adapter to log SOAP requests and responses
Use adapter to authenticate user
Allow specification of which database to use in adapter
Add PHPUnit test for demo adapter
Use adapter to retrieve content list
Use adapter to retrieve content metadata
Use adapter to issue content
Use adapter to retrieve content resources
Use adapter to return content
Delete deprecated ContentHelper

The purpose of ContentHelper was to avoid implementing database queries
in DaisyOnlineService class. After refactoring and implementation of
DemoAdapter the class is deprecated.
Normalize variable name contentId in adapter and service code
Normalize annoucementId and qestionId variable names
Delete sessionUserId variable

DaisyOnlineService does not need to store user id anymore, this shall be
stored in the adapter if necessary.
Document the purpose of sessionUsername
Use adapter in session handling and establishment

If adapter returns false on sessionStart the client/device must
re-establish a session.