list_comments api call improvements

• Improved sql for list_comments
• Removed materialized view from schema: it was not used, it required expensive refreshes
• Some calls are slow comparing to original hived calls
• by_cashout, by_update and by_author_update results are different than expected (waiting for merge from #47 (closed))
• fixed manual tests for list_comments
• Posting a comment will now update active but active is not propagating up at the moment,
• Added post object for database api post
• Added a possibility to convert amount notation to nai notation
• Other minor fixes

hive/indexer/blocks.py

@@ -240,7 +240,7 @@ class Blocks:
 
         if vote_ops is not None:
           for k, v in vote_ops.items():
-              Votes.effective_comment_vote_op(k, v, cls._head_block_date)
+            Votes.effective_comment_vote_op(k, v)
 
         if Posts.comment_payout_ops:
             cls.ops_stats = Blocks.merge_ops_stats(cls.ops_stats, comment_payout_stats)