Issue #406: Feature Request: Tool seam allowance -> Preview (dismine/valentina)

New issue 406: Feature Request: Tool seam allowance → Preview https://bitbucket.org/valentinateam/valentina/issues/406/feature-request-tool-seam-allowance

Bettina G.:

I think it would be nice, to have a preview of the selected points before the creation of the seam allowance is done. It´s very hard to see the selection because, you can only read wich points are selected. A marker in the drawing e. g. mark all selected Points red will be helpful.

For the futute a preview of the seam allowce would be nice, too.