Merge data on single sections
User Story
As a user of HYDWS I need to be able to submit data for the same timeperiod and boreholesections in multiple POST requests so that I have more flexibility and can for example submit data from multiple sources (like 2 geomonitor devices).
Acceptance Criteria
Sending a POST request doesn't overwrite data on a "section" basis, but on a "section data field basis". This means, that if the request contains topflow
for a certain section, and this section already contains data for this timespan, then only the topflow of this section in the timewindow between the first and the last topflow-datapoint of the post request is overwritten.