Add a config option to not shorten UMF messages

[paulwaksmonski]

This would be useful where message sizes do not need to be small.

[cjus]

@paulwaksmonski definitely this is an area that needs work. I also don't love the idea of switching back and forth between short and long form UMF messages. The issue I have with config files is that the behavior can be different between microservices and even instances of a particular microservice potentially leading to interoperability problems. At some level perhaps switching completely to short form might be the solution.

[cjus]

This is currently by designed and won't be fixed.