cleanup

Change-Id: Idc363265021ee3c5cf60781029ca236f295ad8e0
Prepare for release to Sonatype OSS
- change groupId
- add Sonatype OSS parent pom
- add code signing maven plugin

Change-Id: I7031d8e3cea5c4342d3bed201e5c3aedbc4e36bd
Merge branch 'github' into gmaster