feat(element-templates): added "implementationType" property for execution listeners

[AlexanderSkrock]

Supports solving the following issue: bpmn-io/bpmn-js-element-templates#13
Reflects changes in behaviour proposed with: bpmn-io/bpmn-js-element-templates#17

[CLAassistant]

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[akeller]

@barmac @nikku can you please review?

[barmac]

Hi, I'm on it, but want to first merge the documented feature.

[akeller]

Thank you for your submission! We really appreciate it. Like many open source projects, we ask that you sign our Contributor License Agreement before we can accept your contribution.You have signed the CLA already but the status is still pending? Let us recheck it.

Hi @AlexanderSkrock, we had some issues with our CLA over the last few days. Can you please sign it?

[AlexanderSkrock]

Hi @AlexanderSkrock, we had some issues with our CLA over the last few days. Can you please sign it?

I just resigned the CLA and according to pull request checks it seems to be alright now.

Kind regards
Alexander Skrock

[barmac]

This documents precisely what was implemented via bpmn-io/bpmn-js-element-templates#17. The documentation change will apply only to the future releases.

[christinaausley]

@AlexanderSkrock @barmac Are there additional changes here, or are we ready to merge?

[barmac]

If there's 👍 from you then I believe it's ready to be merged :)

[AlexanderSkrock]

I agree with @barmac , all related pull requests are merged.