Move RelC class from HPath.Internal to HPath

src/HPath.hs

@@ -24,6 +24,7 @@ module HPath
   ,Fn
   ,PathParseException
   ,PathException
+  ,RelC
   -- * PatternSynonyms/ViewPatterns
   ,pattern Path
    -- * Path Parsing
@@ -89,6 +90,8 @@ data PathException = RootDirHasNoBasename
   deriving (Show,Typeable)
 instance Exception PathException
 
+class RelC m
+
 instance RelC Rel
 instance RelC Fn