requirements have been checked to be consistent between operational and testing system

Double-check whether requirements are consistent between the operational and the testing system.

Also, find minimal entries that have to go to the file "requirements.txt". This last point, which will be a side product of this issue, is related to #74 (closed).

Sometimes, package updates have to be done to ensure the correct working of the service.
These updates always have to go to the requirements, and they have to be done on both systems (testing and operational) to ensure that they are as equal as possible.