v0.20.0-alpha6

• On macOS, fix set_cursor_visible hides cursor outside of window.
• On macOS, fix CursorEntered and CursorLeft events fired at old window size.
• On macOS, fix error when set_fullscreen is called during fullscreen transition.
• On all platforms except mobile and WASM, implement Window::set_minimized.
• On X11, fix CursorEntered event being generated for non-winit windows.
• On macOS, fix crash when starting maximized without decorations.
• On macOS, fix application not terminating on run_return.
• On Wayland, fix cursor icon updates on window borders when using CSD.
• On Wayland, under mutter(GNOME Wayland), fix CSD being behind the status bar, when starting window in maximized mode.
• On Windows, theme the title bar according to whether the system theme is "Light" or "Dark".
• Added WindowEvent::ThemeChanged variant to handle changes to the system theme. Currently only implemented on Windows.
• Breaking: Changes to the RedrawRequested event (#1041):
  • RedrawRequested has been moved from WindowEvent to Event.
  • EventsCleared has been renamed to MainEventsCleared.
  • RedrawRequested is now issued only after MainEventsCleared.
  • RedrawEventsCleared is issued after each set of RedrawRequested events.
• Implement synthetic window focus key events on Windows.
• Breaking: Change ModifiersState to a bitflags struct.
• On Windows, implement VirtualKeyCode translation for LWin and RWin.
• On Windows, fix closing the last opened window causing DeviceEvents to stop getting emitted.
• On Windows, fix Window::set_visible not setting internal flags correctly. This resulted in some weird behavior.
• Add DeviceEvent::ModifiersChanged.
  • Deprecate modifiers fields in other events in favor of ModifiersChanged.
• On X11, WINIT_HIDPI_FACTOR now dominates Xft.dpi when picking DPI factor for output.
• On X11, add special value randr for WINIT_HIDPI_FACTOR to make winit use self computed DPI factor instead of the one from Xft.dpi.