OverloadedString in source code

[ruhatch]

Right now the pattern docLit $ Text.pack "Some string" is all over the layouting functions. If we enable OverloadedStrings those can all be reduced to docLit "Some string", which would aid readability for complex layouts.

@lspitzner is there a specific reason not to use OverloadedStrings or did you just not choose to. Do you think it makes sense to enable it in a few files?

[tfausak]

I can't speak for Lennart, but I sometimes avoid OverloadedStrings because I'm not comfortable with how ByteStrings behave. That being said, it's usually worth the convenience to me.