calling all binding and not only the first one

[typemytype]

https://github.com/robotools/vanilla/blob/master/Lib/vanilla/vanillaWindows.py#L465-L466

https://forum.robofont.com/topic/610/tracking-resize-event-for-current-glyph-window

[typemytype]

the return value is only used on should close

I would propose to call all callbacks and collect all return values. Return values must be True or False. This makes it possible to merge it down to a single return value:

• all True -> True
• mixed -> False
• all False -> False

all(collectedReturnValues)