cross compile for scala 2.12.0-M4. Also remove -target:jvm-1.6 scalacOptions

Author: giabao

project/Common.scala

@@ -16,12 +16,11 @@ object Common {
       // Core settings
       organization := "com.typesafe.scala-logging",
       scalaVersion := Version.scala,
-      crossScalaVersions := List(scalaVersion.value),
+      crossScalaVersions := Version.crossScala,
       scalacOptions ++= List(
         "-unchecked",
         "-deprecation",
         "-language:_",
-        "-target:jvm-1.6",
         "-encoding", "UTF-8"
       ),
       unmanagedSourceDirectories in Compile := List((scalaSource in Compile).value),

project/Dependencies.scala

@@ -4,6 +4,7 @@ object Version {
   val logback   = "1.1.7"
   val mockito   = "1.9.5"
   val scala     = "2.11.8"
+  val crossScala = List(scala, "2.12.0-M4")
   val scalaTest = "2.2.6"
   val slf4j     = "1.7.21"
 }