scala style setting

build.sbt

lazy val compileScalastyle = taskKey[Unit]("compileScalastyle")

// scalastyle >= 0.9.0
compileScalastyle := scalastyle.in(Compile).toTask("").value

(compile in Compile) := ((compile in Compile) dependsOn compileScalastyle).value

assemblyMergeStrategy in assembly := {
  case PathList("META-INF", xs @ _*) => MergeStrategy.discard
  case x => MergeStrategy.first
}