Update for new Signing Service

[vborger-p4u]

Hi!
We are using this package and we have to switch to the new signing service version. Within the new update the client sign function i sno longer working. I already have a fix for that but i need permissions to create a pull request :)

[JanSlabon]

Can you share details? We're not aware of special permissions for creating a PRs in this repo?

[vborger-p4u]

I am sorry. I am not able to push my branch. Creating a PR would be possible i guess.