Add ScalaCheck to build.sbt

Author: ashawley

build.sbt

@@ -32,6 +32,8 @@ libraryDependencies += "junit" % "junit" % "4.11" % "test"
 
 libraryDependencies += "com.novocode" % "junit-interface" % "0.10" % "test"
 
+libraryDependencies += "org.scalacheck" %% "scalacheck" % "1.13.2" % "test"
+
 //// testing:
 // used in CompilerErrors test
 libraryDependencies += ("org.scala-lang" % "scala-compiler" % scalaVersion.value % "test").exclude("org.scala-lang.modules", s"scala-xml*")