Introducing GF.Text.Pretty for more concise pretty printers and GF.Infra.Location for modularity

GF.Text.Pretty provides the class Pretty and overloaded versions of the pretty
printing combinators in Text.PrettyPrint, allowing pretty printable values to
be used directly instead of first having to convert them to Doc with functions
like text, int, char and ppIdent. Some modules have been converted to use
GF.Text.Pretty, but not all. Precedences could be added to simplify the pretty
printers for terms and patterns.

GF.Infra.Location contains the types Location and L, factored out from
GF.Grammar.Grammar, and the class HasSourcePath. This allowed the import
of GF.Grammar.Grammar to be removed from GF.Infra.CheckM, making it more
like a pure library module.

src/compiler/SimpleEditor/Convert.hs

@@ -6,7 +6,7 @@ import Data.List(sortBy)
 import Data.Function(on)
 import qualified Data.Map as Map
 import Text.JSON(makeObj) --encode
-import Text.PrettyPrint(render,text,(<+>))
+import GF.Text.Pretty(render,(<+>))
 
 import qualified Data.ByteString.UTF8 as UTF8(fromString)
 
@@ -124,11 +124,11 @@ convCncJment (name,jment) =
     ResOper oltyp (Just lterm) -> return $ Op $ Oper lhs rhs
       where
         lhs = i++maybe "" ((" : "++) . render . ppTerm q 0 . unLoc) oltyp
-        rhs = render (text " ="<+>ppTerm q 0 (unLoc lterm))
+        rhs = render (" ="<+>ppTerm q 0 (unLoc lterm))
     ResOverload [] defs -> return $ Op $ Oper lhs rhs
       where
         lhs = i
-        rhs = render $ text " = overload"<+>ppTerm q 0 r
+        rhs = render $ " = overload"<+>ppTerm q 0 r
         r =  R [(lab,(Just ty,fu)) | (L _ ty,L _ fu) <-defs]
         lab = ident2label name
     CncFun _ (Just ldef) pprn _ -> -- ignores printname !!