* PipingSurfaceLinesCsvReader.GetLineCount throws exceptions when file has invalid header * Extended testcoverage for PipingSurfaceLineCsvImporter for these error cases Related to Issue [WTI-20]git-svn-id: https://repos.deltares.nl/repos/WettelijkToetsInstrumentarium/trunk@342 5a3db67b-de53-47b5-99c8-a1c30a6650e2Former-commit-id: 0d664432440741f6e99e9542a1840838ed2f748e