Unhack deprojetivization, moving it into pipeline

Previously the deprojectivize() call was attached to the transition
system, and only called for German. Instead it should be a separate
process, called after the parser. This makes it available for any
language. Closes #898.

spacy/language.py

@@ -144,6 +144,7 @@ class BaseDefaults(object):
             pipeline.append(nlp.tagger)
         if nlp.parser:
             pipeline.append(nlp.parser)
+            pipeline.append(Pseudoprojectivity.deprojectivize)
         if nlp.entity:
             pipeline.append(nlp.entity)
         return pipeline

spacy/syntax/arc_eager.pyx

@@ -427,8 +427,6 @@ cdef class ArcEager(TransitionSystem):
 
     def finalize_doc(self, doc):
         doc.is_parsed = True
-        if doc.vocab.lang == 'de':
-            PseudoProjectivity.deprojectivize(doc)
 
     cdef int set_valid(self, int* output, const StateC* st) nogil:
         cdef bint[N_MOVES] is_valid