Release version 1.1.1

* Migrate to go mod
* Use SHA256 for certificate fingerprinting
* Migrate to zap for logging
* Add gosec linting

Release version 1.1.0

* Add S3 bucket support for config storage
* Fix a bug with stale metrics removal when reloading configs

Release version 1.0.1

* Add SHA1 certificate fingerprint as a label to exported metrics.

Release version 1.0.0

* Change config format to allow grouping domains into service pools.
Beware, this is a breaking change, this version won't work with old
config formats.

Release version 0.3

* Add reload configs on SIGHUP signal feature.

Release version 0.2

* Add multiple config files support
* Add support for labels and references in config files.

Release version 0.1

* Initial release