* Move DeviceEvent handling to the message target window.
Previously, device events seem to have only been sent to one particular
window, and when that window was closed Winit would stop receiving
device events. This also allows users to create windowless event loops
that process device events - an intriguing idea, to say the least.
* Emit LWin and RWin VirtualKeyCodes on Windows
* Implement ModifiersChanged on Windows
* Make ModifiersChanged a tuple variant instead of a struct variant
* Add changelog entries
* Format
* Update changelog entry
* Fix AltGr handling
* Reformat
* Publicly expose ModifiersChanged and deprecate misc. modifiers fields