Replicate the bnd defaults from maven-bundle-plugin

[rocketraman]

The defaults from the maven bundle plugin (see the section "Default Behavior" here: http://felix.apache.org/site/apache-felix-maven-bundle-plugin-bnd.html) are pretty intuitive and anyone who has used maven-bundle-plugin (which is pretty much everyone in the java/osgi world) will be familiar with them.

I suggest that SBT-OSGi should re-use the same defaults, as a principle of least surprise, and since they do make good intuitive sense.

[briantopping]

+1

[hseeberger]

PRs are very welcome!