* This means that all APIs pass byte string types. ALL strings everywhere
in the entire codebase must be assumed to be and treated as UTF-8 content
not ASCII.
* Gets rid of all the horrible %hs specifiers that caused warnings on
linux! Hooray.
* We convert to wide strings, or use wide characters, only when necessary
to use the Win32 API. Some windows specific code will stay in wide chars
just for convenience.
* Files are already serialised as UTF-8 strings for linux/windows binary
compatibility, so this change doesn't break backwards compatibility.