* correct tree in ud treebank

- needs Extend's EmbedSSlash

* (Por) add EmbedSSlash

* (Por) change verb form for RPasse AAnter
the current linearization of RPasse Anter tense combination is not
grammatical Portuguese, while the auxiliar in the present + participle
past form is not available anywhere (it is grammatical Portuguese but
not as common as simple past, which gets the RPast ASimul
linearization)

src/spanish/ExtendSpa.gf

@@ -5,6 +5,7 @@ concrete ExtendSpa of Extend = CatSpa ** ExtendRomanceFunctor -
  CompoundAP,
  CompoundN,
  ExistsNP,
+ EmbedSSlash,
  GenRP,
  GenRP,
  IAdvAdv,