v0.1.10

[0.1.10] - 2021-08-25

Added

• Added keyboard control of tree control
• Added Widget.gutter to calculate space between renderable and outside edge
• Added margin, padding, and border attributes to Widget

Changed

• Callbacks may be async or non-async.
• Event handler event argument is optional.
• Fixed exception in clock example #52
• Added Message.wait() which waits for a message to be processed
• Key events are now sent to widgets first, before processing bindings