txt and rtf extension support

Text files and Rich Format files can now be drag-and-dropped into SOAPware, and they will be editable directly in SOAPware.

User request.

Previously the types were allowed to be drag-and-dropped, but the editing happened outside of SOAPware.  This is a change so the documents can now be edited directly without the need for an external program to be launched.

Open a chart.

Make sure an editable docutainer is open.

Drag a File with a .txt or .rtf extension to the document tabs area, and Drop.

Once the file is drag-and-dropped into SOAPware, any changes to the original file will not be reflected in the file copied into SOAPware. Likewise, any changes of the file copied into SOAPware will not be reflected in the original file that remains outside of the chart.