[Haskell-cafe] stack setup errors when user name has accents

[Phil Ruffwind]

> *"Could not parse 'C:\Users\Andr├®\AppData\Roaming\stack\config.yaml':*
> *InvalidYaml (Just (YamlException "Yaml file not found: 
> C:\\Users\\Andr\233\\AppData\\Roaming\\stack\\config.yaml"))*
> 
> *See http://docs.haskellstack.org/en/stable/yaml_configuration/."*

I think the accented letter is displayed as “├®” because GHC renders all
Unicode strings using UTF-8, regardless of what the console codepage is.
 When the UTF-8 encoded letter is shown in codepage 850, it will produce
this incorrect display.

That being said, the presence of `\233` (the Unicode code point for the
accented e) suggests that internally it is correctly storing the
accented letter.  Since the yaml library uses
System.Posix.Internals.c_open, which does claim to handle Unicode
properly on Windows, I'm actually confused why it doesn't work.  Maybe
the problem is not with the yaml library?