msgpack fails on Java 10 because of transitive dep

[ghadishayban]

Only when you instantiate a :msgpack writer do you get a ClassNotFoundException.

problematic dependency chain:

transit-java -> msgpack -> Javassist -> jdk.jdi module

In the module system, module jdk.jdi is not included in the default java.se module, it must be specified with --add-module

It appears that the underlying msgpack library shed the javassist dependency on the 0.8 series of releases.