Latvian: CN and NP types are extended with a Bool field for tracking whether a relative clause has been used

This is used for inserting the closing comma if necessary, and later will be used also for adjusting the word order.

src/latvian/SentenceLav.gf

@@ -78,6 +78,7 @@ oper
           Deb _ _ => np.s ! Dat ;  --# notpresent
           _       => np.s ! vp.leftVal
         } ++
+        closeRelCl np.isRel ++        
         buildVerb vp.v mood pol agr np.pol vp.rightPol ++  -- verb
         vp.compl ! np.agr                                  -- object(s), complements, adverbial modifiers
     } ;