upgrade kafka client to 2.3.0

Bump version and add changelog entry (#325)

remove obsolete option ssl (#304)

Version Bump and changelog entry

Fixes #302

bump to 8.3.0

update dependencies to accommodate new kafka-client 2.1.0 needs

Update version and add changelog entry

Also updated license info in gemspec to be SPDX compliant.

Fixes #295

fix documentation about kafka client version

version and changelog bump for startup/shutdown crash fix

bump to 8.1.0 and update compatibility matrix doc

fix broken 8.0.5 release