Under WSL, Python in text mode will translate `\n` into `\r\n`, even
though other tools and utilities use `\n` (because WSL is basically
Linux). This leads to the update scripts leaving the files with
Windows newlines even though git and similar expect them to have
Linux newlines.
By instead handling files in binary mode, we can keep the original
newlines. This commits switches parts of the update process to
binary mode, but not all because some of the will require a lot of
work to fix.
06bc20cf37