fix #179 Turn extra and adapter into valid OSGI bundles
fix #179 Turn extra and adapter into valid OSGI bundles

This commit introduces BND to make reactor-extra and reactor-adapter
valid OSGI bundles. For simplicity, each project is individually
configured using a bnd block in the gradle build, rather than via a bnd
file.

Closes #180

reactor/reactor-extensions,reactor/reactor-extensions,reactor/reactor-extensions,reactor/reactor-extensions