Set version to 0.6.0-SNAPSHOT
Fix execution order of tasks in dockerBuildAndPush
Merge branch 'master' into auto-plugin

Conflicts:
	build.sbt
	src/main/scala/sbtdocker/Plugin.scala
Release version 0.5.1
Don't push if build fails in dockerBuildAndPush task
Release version 0.5.2
Merge branch 'master' into auto-plugin

Conflicts:
	build.sbt
	src/main/scala/sbtdocker/Plugin.scala