Implement an intention action to move a companion object member to top level

#KT-18828 Fixed

(cherry picked from commit 11f8f8b)

idea/testData/intentions/moveMemberToTopLevel/functionInCompanion.kt

@@ -0,0 +1,7 @@
+// WITH_RUNTIME
+
+class A {
+    companion object {
+        private fun <caret>foo() = 1
+    }
+}