Add OSGi Manifest headers to riak-pb jar file

[mattbishop]

In order to use the protocol buffer client in an OSGi environment, the jar file needs a specific set of headers in the MANIFEST.MF file. These are usually generated during the build.

I can write a patch to do so.

[mattbishop]

Will anyone mind if I update the protobuf maven plugin to one that is available on Maven Central? The one in this pom has to be built and installed before this build will work.

[mattbishop]

Here is a related fixed issue in Google's protobuf java project. Yay, almost there for running the riak client in OSGi!

http://code.google.com/p/protobuf/issues/detail?id=298