true singleton object.

Reviewed by Gregor Lingl.

reviewers: Georg, Benjamin

menu entries were not deleted.

Tcl command objects.

Thanks to Wummel for the patch

This improves compatibility with Tcl 8.5, which would
otherwise return textindex objects.

Will backport to 2.5.

if an exception occurs.
Will backport to 2.5.

the parent window is withdrawn. This mirrors what dialog.tcl
does.
Will backport to 2.5.

when the module is launched as a script.

Make begin_fill idempotent.
Update demo2 to demonstrate filling of concave shapes.

degrees and radians.

filling of arcs. Also fixes #1514693.

Fixes #1514703