Nowadays most of the loadbalancing is done on the server-side and hence
there is only a single datafile URL (and other URLs) inside the
boostrap.json.
The features of the CUrlList are hence not really used. This is also a
step into removing CUrl and using QUrl instead, to avoid maintaining a
separate URL class.
With this, the database debug flag can only be activated when using swift
with a development build. Setting the development flag in the json also
didn't worked previously as expected because the corresponding function
to get the flag in application.cpp was called before the setup was loaded.
