Bump to 2.2.0 for release

Bump version to 2.1.1

Bump to 2.1.0

Update CHANGELOG, bump version

Bump version to 2.0.2, changelog update

Bump version to 2.0.1

Update changelog

Merge pull request bigcommerce#27 from splittingred/i26

bigcommerce#26: Fix issue with field errors being persisted between calls

Comment updates, fix rubocop

Guard clause for invalid method calls when checking streaming state