lets bijection-util be distributed

## motivation
Try running ```sbt 'project bijection-util' publish-local``` and then unpacking the jar without this change.  Then try the same, except after this change has been applied.  Feel free to try wgetting [sonatype](https://oss.sonatype.org/content/groups/public/com/twitter/bijection-util_2.10/0.5.0/bijection-util_2.10-0.5.0.jar).

## implementation
there was a mismatch between osgiExportAll's concept of what the package name was, and what the package name actually was, which meant that none of the packages were being put into the jar.  They have been unified under twitter_util.