KotlinCompiler and tests aware on standard library

stdlib/ktSrc/JavaUtil.kt

@@ -0,0 +1,11 @@
+namespace std
+
+namespace util {
+    import java.util.*
+
+    val Collection<*>.size : Int
+        get() = size()
+
+    val Collection<*>.empty : Boolean
+        get() = isEmpty()
+}

stdlib/ktSrc/StandardLibrary.kt

@@ -1,15 +1,5 @@
 namespace std
 
-namespace util {
-    import java.util.*
-
-    val <T> Collection<T>.size : Int
-        get() = size()
-
-    val <T> Collection<T>.empty : Boolean
-        get() = isEmpty()
-}
-
 namespace io {
     import java.io.*
     import java.nio.charset.*