Feature/merge

As current usage of HYDWS will probably mean receiving data in a file format, which will then have to be fed to the database, merging facilities are required. A borehole will not be created every time the import script is used, instead the hydraulics and other data are merged. Most of the logic has been taken from RAMSIS with some alterations given the different db and orm structure. Tests are available for the merging facilities and there is a higher level test that makes system calls to the load json entry point.