Removed obsolete piping code. Note that reading VNK and 4Forces from input xml is kept in order to be able to give a nice "not implemented error".Related to Issue [MWDAM-1922]
Made sure that in the manual, the is_aquifer column for the soilprofiles.csv is now requuired and no longer optional. There should always be at least one aquifer layer per profile in order to perform a valid calculation. Related to Issue [MWDAM-1651]