Pop Ranker for ODQA

Created by: my-master

• add Pop Ranker for doc_retrieval and odqa
• change doc splitting strategy from "chunks" to "paragraphs" for configs without Pop Ranker, for the best f1

deeppavlov/configs/odqa/en_odqa_pop_infer_enwiki20180211.json

@@ -8,7 +8,7 @@
     ],
     "pipe": [
       {
-        "config_path": "{CONFIGS_PATH}/doc_retrieval/en_ranker_pop_wiki.json",
+        "config_path": "{CONFIGS_PATH}/doc_retrieval/en_ranker_pop_enwiki20180211.json",
         "in": [
           "docs"
         ],
@@ -86,4 +86,4 @@
     "download": [
     ]
   }
-}
\ No newline at end of file
+}