Refactor Echo::{Request, Reply}.
Merge pull request #85 from trema/feature/refactor_echo

Refactor Echo::{Request, Reply}.
Add HoundCI configuration file.
Remove Format.create_from methods.
Remove unnecessary private method.
Merge pull request #86 from trema/feature/refactor_echo

Remove Format.create_from methods.
Refactor Hello.new.
Refactoring.
Refactor FEATURES_REPLY.
Refactor features message classes.
Merge pull request #87 from trema/feature/refactor_hello

Feature/refactor hello
Fix broken guard notification config.
Merge pull request #88 from trema/feature/guard

Fix broken guard notification config.
Refactor features request.
Merge pull request #89 from trema/feature/refactor_features_request

Refactor features request.
Refactor features reply.
Refactor features reply.
Merge pull request #90 from trema/feature/refactor_features_reply

Feature/refactor features reply
Try to overwrite HoundCI's default RuboCop setting to reduce the `Prefer
double-quoted strings...` comments.
Refactor Features::Reply.