Update extract module regexp for unicode quotes

GHC-7.8.x uses U+2018 and U+2019 for quotes.

Also do not call ghc-resolve-document-path if module cannot be extracted
in case of local functions.
Fixing a race (#405).
Yet another fix for #405.
Merge pull request #409 from iquiw/master

Update extract module regexp for unicode quotes
Limit overlays to actual position of error