V07 add jackson dataformat

See https://github.com/msgpack/msgpack-java/issues/145
Add a version setting (e.g., `version="0.1-SNAPSHOT") here if you want to make the release cycle of msgpack-jackson independent from msgpack-core. 

It is also possible to create a separate build.sbt file under msgpack-jackson folder, and use a project reference setting here if we need to import the msgpack-jackson/build.sbt:
http://stackoverflow.com/questions/11653435/how-to-reference-external-sbt-project-from-another-sbt-project