[maven-release-plugin] prepare for next development iteration
Merge branch 'release/v2.2.1' into develop
allow negative amount payments
Merge remote-tracking branch 'origin/negative_amount_payment_hotfix' into develop
[maven-release-plugin] prepare release v2.2.2
Merge tag 'v2.2.2'

[maven-release-plugin] copy for tag v2.2.2