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/text/RegexTest/replaceEvaluator.kt

@@ -0,0 +1,10 @@
+import kotlin.text.*
+
+import kotlin.test.*
+
+
+fun box() {
+    val input = "/12/456/7890/"
+    val pattern = "\\d+".toRegex()
+    assertEquals("/2/3/4/", pattern.replace(input, { it.value.length.toString() } ))
+}