Error ".then is not a function" when using widget

[osfrance]

Hi,
When using Windget I had this error : TypeError: mp.http.makeRequest(...).then is not a function

I submit a Pull request #1 fot solving this.

Thanks,

[aarranz]

This is because this operator is targeting WireCloud 1.1 where .then is available. But I don't see any problem using the onSuccess, onFailure and onComplete callbacks to be backwards compatible with older versions of WireCloud.