* Defined additional error conditions in PipingSurfaceLinesCsvReader related to the filepath. * Handling error conditions related to filepath by PipingSurfaceLinesCsvImporter. Related to Issue [WTI-20] git-svn-id: https://repos.deltares.nl/repos/WettelijkToetsInstrumentarium/trunk@330 5a3db67b-de53-47b5-99c8-a1c30a6650e2