Extend close() to helpbrowser, xcos, browsevar and editvar GUIs
Reported by Samuel GOUGEON (@sgougeon)
BUG DESCRIPTION:
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Besides figures and graphical bars, there is presently no easy way to close other GUIs like the helpbrowser, xcos and browsevar with an instruction, only interactively.
close() could be extended with the following syntaxes:
close help
close xcos
close xcos!
close editvar
close browsevar
"close xcos" and "close xcos!" will close all opened diagrams.
"close xcos" will ask for confirmation if any edited diagram has some unsaved changes, while
"close xcos!" will close all diagrams anyway.