Extract Function: Add support of property-as-function calls

#KT-5179 Fixed

idea/testData/refactoring/extractFunction/parameters/misc/variableAsFunction.kt

@@ -0,0 +1,9 @@
+// PARAM_TYPES: A
+class A {
+    fun invoke() = 20
+}
+// SIBLING:
+fun testProp() {
+    val foo = A()
+    <selection>foo()</selection>
+}