* Remove UnownedWindow::inner_rect
* Refactor custom view to use much less `unsafe`
The compiler fence is safe to get rid of now since `interpretKeyEvents` takes `&mut self`
* Refactor Window to use much less unsafe
* Refactor NSApplication usage to have much less unsafe
* Remove cocoa dependency
* Enable `deny(unsafe_op_in_unsafe_fn)` on macOS
Also re-enable clippy `let_unit_value` lint
* Remove #[macro_use] on macOS
* Refactor window delegate to use much less unsafe
* Begin abstraction over AppKit
* Clean up NSApplication delegate declaration
* Clean up NSApplication override declaration
* Clean up NSWindow delegate declaration
* Clean up NSWindow override declaration
* Clean up NSView delegate declaration
