More tweaks to smart quote parsing: a ' is not a single quote

start if followed by 's' and then a non-alphanumeric.  (Yes,
this is English-centric, I'm afraid.  But it does help, and I
can't think of a language in which 's' by itself is a word.)


git-svn-id: https://pandoc.googlecode.com/svn/trunk@498 788f1e2b-df1e-0410-8736-df70ead52e1b

src/Text/Pandoc/Readers/Markdown.hs

@@ -778,6 +778,7 @@ singleQuoteStart = try $ do
   failIfInQuoteContext InSingleQuote
   char '\'' <|> char '\8216'
   notFollowedBy (oneOf ")!],.;:-? \t\n")
+  notFollowedBy (do{char 's'; satisfy (not . isAlphaNum)})
 
 singleQuoteEnd = try $ do
   char '\'' <|> char '\8217'