Merge pull request #41 from Bouke/fix/readcallback

Fix for regression with CoreFoundation 5.3

Merge pull request #36 from Bouke/linux-swift-53

Test against Swift 5.3 on Linux

Resolve code style violations

Merge pull request #32 from Bouke/swift-5

Changelog for 0.5

Default delegate implementation

Keep a changelog

Depend on new DNS release

Update DNS dependency

Test cases belong to DNS