Test data split between compiledJava tests and compiledKotlin tests

Basically, this commit splits test data from the from java-txt-kt to two pairs java-txt and kt-txt.
This commit leads to some duplication in test data.
This is temporary: in the platform types branch the test data for LoadJava tests will be changed dramatically, so duplication will go away

compiler/testData/loadJava/compiledJava/kotlinSignature/MethodWithMappedClasses.java

@@ -0,0 +1,12 @@
+package test;
+
+import java.lang.UnsupportedOperationException;
+import java.util.*;
+import jet.runtime.typeinfo.KotlinSignature;
+
+public class MethodWithMappedClasses {
+    @KotlinSignature("fun <T> copy(dest : MutableList<in T>, src : List<T>)")
+    public <T> void copy(List<? super T> dest, List<T> src) {
+        throw new UnsupportedOperationException();
+    }
+}