Case-insensitive changelog file extension check

It is not uncommon to have files like NEWS.TXT.

Author: wismill

src/Distribution/Server/Packages/ChangeLog.hs

@@ -8,9 +8,9 @@ import Data.Char as Char
 
 
 isChangeLogFile :: FilePath -> Bool
-isChangeLogFile fname = map Char.toLower base `elem` basenames
+isChangeLogFile fname = base `elem` basenames
                         && ext `elem` extensions
   where
-    (base, ext) = splitExtension fname
+    (base, ext) = splitExtension (map Char.toLower fname)
     basenames  = ["news", "changelog", "change_log", "changes"]
     extensions = ["", ".txt", ".md", ".markdown"]