Renamed entry point and exit point to the dike toe at river and dike toe at polder and their dutch translations as this better fits the model of surface lines. Added characteristic points for demo project. Changed the TemporaryImportFile so that it supports multiple files which are required by file importers. Related to Issue [WTI-380] git-svn-id: https://repos.deltares.nl/repos/WettelijkToetsInstrumentarium/trunk@2193 5a3db67b-de53-47b5-99c8-a1c30a6650e2