tests: Copy stdlib tests from Kotlin/JVM

This patch copies Kotlin/JVM stdlib tests (libraries/stdlib/test)
excepting ones with explicit java dependencies. It also transforms
the tests to use them as box-tests.

backend.native/tests/external/stdlib/collections/CollectionTest/dropLast.kt

@@ -0,0 +1,13 @@
+import kotlin.test.*
+import kotlin.comparisons.*
+
+fun box() {
+    val coll = listOf("foo", "bar", "abc")
+    assertEquals(coll, coll.dropLast(0))
+    assertEquals(emptyList<String>(), coll.dropLast(coll.size))
+    assertEquals(emptyList<String>(), coll.dropLast(coll.size + 1))
+    assertEquals(listOf("foo", "bar"), coll.dropLast(1))
+    assertEquals(listOf("foo"), coll.dropLast(2))
+
+    assertFails { coll.dropLast(-1) }
+}