https://github.com/kovidgoyal/kitty/releases/tag/v0.17.1
The png2icns patch is no longer needed because kitty will now automatically use `png2icns` when `iconutil` cannot be found.
The zsh completions will now work without needing to invoke them with `source`, which means, that we can just install them like the other shell completions.
Install the `kitty` command-line utility and the `kitty.app` macOS
application.
* Prefer libicns (png2icns) over Apple's non-free iconutil.
* Work around warnings from Apple headers by disabling -pedantic-errors
and -Werror.
* Work around ld not support LLVM-LTO by disabling LTO.
* Make Kitty and glfw compile for macOS 10.11 (and macOS 10.10).