Add tests for Tuple2 (normal and specialized)

Now, we support pickling and unpickling specialized tuples. It's
necessary to add a special method to check class equality since the
specialized classes are implemented as subclasses and therefore have its
own class name, failing a simple class equality.

Author: jvican

core/src/test/scala/scala/pickling/generation/pickler/Tuple2Pickler.scala

@@ -0,0 +1,28 @@
+package scala.pickling.generation.pickler
+
+import org.scalatest.FunSuite
+
+import scala.pickling._
+import Defaults._
+import json._
+import scala.pickling.util.ClassMapper
+import static._
+
+class Tuple2Pickler extends FunSuite {
+
+  test("pickle/unpickle (Int, String)") {
+    val t = (1, "")
+    val t2 = t.pickle.unpickle[(Int, String)]
+    assert(t === t2)
+  }
+
+  test("pickle/unpickle any specialized tuple like (Int, Int)") {
+    val t = (1, 2)
+    val clz = classOf[(Int, Int)]
+    val clzT = t.getClass
+    println(ClassMapper.areSameClasses(clzT, clz))
+    val t2 = t.pickle.unpickle[(Int, Int)]
+    assert(t === t2)
+  }
+
+}