Overhaul device events API and add gamepad support on Windows (#804)

* Initial implementation

* Corrected RAWINPUT buffer sizing

* Mostly complete XInput implementation

* XInput triggers

* Add preliminary CHANGELOG entry.

* match unix common API to evl 2.0

* wayland: eventloop2.0

* make EventLoopProxy require T: 'static

* Revamp device event API, as well as several misc. fixes on Windows:

* When you have multiple windows, you no longer receive duplicate device
  events
* Mouse Device Events now send X-button input
* Mouse Device Events now send horizontal scroll wheel input

* Add MouseEvent documentation and Device ID debug passthrough

* Improve type safety on get_raw_input_data

* Remove button_id field from MouseEvent::Button in favor of utton

* Remove regex dependency on Windows

* Remove axis filtering in XInput

* Make gamepads not use lazy_static

* Publicly expose gamepad rumble

* Unstack DeviceEvent and fix examples/tests

* Add HANDLE retrieval method to DeviceExtWindows

* Add distinction between non-joystick axes and joystick axes.

This helps with properly calculating the deadzone for controller
joysticks. One potential issue is that the `Stick` variant isn't used
for *all* joysticks, which could be potentially confusing - for example,
raw input joysticks will never use the `Stick` variant because we don't
understand the semantic meaning of raw input joystick axes.

* Add ability to get gamepad port

* Fix xinput controller hot swapping

* Add functions for enumerating attached devices

* Clamp input to [0.0, 1.0] on gamepad rumble

* Expose gamepad rumble errors

* Add method to check if device is still connected

* Add docs

* Rename AxisHint and ButtonHint to GamepadAxis and GamepadButton

* Add CHANGELOG entry

* Update CHANGELOG.md

* Add HidId and MovedAbsolute

* Fix xinput deprecation warnings

* Add ability to retrieve gamepad battery level

* Fix weird imports in gamepad example

* Update CHANGELOG.md

* Resolve francesca64 comments

tests/send_objects.rs

@@ -22,6 +22,8 @@ fn window_send() {
 fn ids_send() {
     // ensures that the various `..Id` types implement `Send`
     needs_send::<winit::window::WindowId>();
-    needs_send::<winit::event::DeviceId>();
+    needs_send::<winit::event::device::MouseId>();
+    needs_send::<winit::event::device::KeyboardId>();
+    needs_send::<winit::event::device::GamepadHandle>();
     needs_send::<winit::monitor::MonitorHandle>();
 }