v0.13.0

What's Changed

• fix: instance variable @errors not initialized by @supercaracal in #409
• perf: use case-insensitive comparison instead of normalization for command names by @supercaracal in #410
• fix: make no-concurrency mode default by @supercaracal in #411
• build: release 0.13.0 by @supercaracal in #412

Full Changelog: v0.12.1...v0.13.0