v4.1.0

New features:

• Added close function for Window (#78 by @jmp-0x7C0)
• Added visibilityState for HTMLDocument (#79 by @garyb)

Other improvements:

• Added purs-tidy config and format checking (#79 by @garyb)
• HTMLDocument's FFI is now implemented in terms of EffectFn (#79 by @garyb)