Make batch size configurable.
Merge pull request #186 from EasonLiao/config_batch_size

Make batch size configurable.
Remove round robin election.
Merge pull request #184 from EasonLiao/remove_round_robin

remove round robin election
Some changes on doc.

1. Fix the url(from branch to version) problem.
2. Add workflow git pic.
Merge pull request #188 from EasonLiao/doc

Some changes on doc.