Refactor build and release process
Refactor build and release process

* Automatically sign and release for sonatype.
* Execute findbugs on reporting stage instead of build
  (because our jenkins fails on findbugs for some reason...)

ryancox/docker-maven-plugin,davidkarlsen/docker-maven-plugin,lndbrg/docker-maven-plugin,velo/docker-maven-plugin,seven10builder/docker-maven-plugin,UpSport/docker-maven-plugin,kevin-canadian/docker-maven-plugin,zpearce/docker-maven-plugin,spotify/docker-maven-plugin,gilles/docker-maven-plugin,ravwojdyla/docker-maven-plugin,aharonha/docker-maven-plugin,HotelsDotCom/docker-maven-plugin