p300 project mavenized

HI,

following is included in the pull request and can be cherry picked.
- the project has been mavenized, `mvn package` will create the executable jar file
- OS X callback classes included from p300.eu
- changes some test classes to JUnit4 syntax to be able to use @Ignore for some of them
- jmdns is included as the default multi-cast DNS implementation, the DNSSDHelperHook implementations loaded via service-provider loading facility

cheers
Frank