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Issue Description

The kafka.Event only implement GetHeaders ,GetHeader. And everything else (GetHeaderByteSlice,GetHeadeString GetHeaderInt) goes to empty basic implement nuclio.AbstractEvent that return empty value.

Expected Behavior

It should return value from existed header data.

Deployment Method

Docker

Nuclio Version

1.14.1

Additional Information

Also its kind surprising behavior and design to void any unimplemented/new feature as default, if user doesn't look into base code no one would know what actually going on, and maintainer won't even notice there existed the new method not even implemented. :/