This branch introduces hybrid operations. This type of operations can
have some fields defined in old or new way. Depending on node to which
we want send the operation.

Scheduled weekly dependency update for week 37

Remove tiny typo

Excuse the small PR, I just saw the typo while browsing through the documentation.

response format handling and minor other things

account.py: use only Discussions_by_* for blog/comment history, improving condenser API compatibility

* Fix non ascii text handling on some nodes
* Add STEEM_REVERSE_AUCTION_WINDOW_SECONDS_HF21 constant
* Fix get_curation_rewards

Scheduled weekly dependency update for week 34

Add support for Pulsar to be used in future EFTG iterations

* add options use_tags_api to use database api to get comments
* fix get_similar_account_names
* add more try expect to fail back to condenser api

* operations for account_update2, create_proposal, update_proposal_votes and remove_proposal were added
* update_proposal_votes was added to steem
* update_account_jsonmetadata was added to account
* new beempy delete were added