Properly and consistently handle file path quoting for GHCi :commands
Properly and consistently handle file path quoting for GHCi :commands

- Quote all paths with ""
- Escape only \ and "
- Don't rely on %S elisp string escaping
- Remove special-case handling for :move

This allows all commands to safely handle Windows paths and both
directory paths and filenames which contain spaces on any platform.

chrisdone/intero,chrisdone/intero,commercialhaskell/intero,commercialhaskell/intero,chrisdone/ghci-ng,commercialhaskell/intero,chrisdone/ghci-ng,chrisdone/intero