Plugins using the flat file parser should warn about complex column mappings
Most mappings are from a single file column to a single data base column, ie. \Row\ The flat file parser allows combined mappings that can use multiple columns and/or constant strings in any combination, ie. \Row\,\Coloumn\
This kind of mapping is unusual and in three recent cases it was an error (an extra space or slash at the end of the column mapping).
By default, plugins should only allow the simple case and return an error message in the complex case. Then, a user may correct an incorrect mapping or use an extra parameter to specify if the complext mapping should be allowed or not.
See also ticket #563.