Export file type

[Robert Schleif]

When you click on the Write button in the Export transform, a directory window, apparently generated by the operating system, appears in which a file name is provided. For my settings, generally the provided file name is not the file type that export will be saving too. It would be less confusing if it were possible for the file name that is provided were *.* or blank altogether, or could always be of the file type that Export is going to save.

[jsachs]

Fixed for next release