Introduce a generic IDataStoreAgent implementation

• Add makeDataStoreAgent which takes a callable (eg. a lambda) and creates an instance of a class which inherits from IDataStoreAgent, and which implements IDataStoreAgent::analyse by invoking the callable
• Extend the IDataMgrSvc interface so that where it accepts an IDataStoreAgent, it also accepts a callable with the signature which matches the signature of IDataStoreAgent::analyse
• Replace some IDataStoreAgent implementations with lambdas