Code Insight: "Generate secondary constructor" action

#KT-6970 Fixed

idea/testData/codeInsight/generate/secondaryConstructors/supers.kt.after

@@ -0,0 +1,20 @@
+// ACTION_CLASS: org.jetbrains.kotlin.idea.actions.generate.KotlinGenerateSecondaryConstructorAction
+open class Base(n: Int) {
+    constructor(a: Int, b: Int): this(a + b)
+}
+
+class Foo : Base {
+    val x = 1
+
+    <caret>constructor(a: Int, b: Int) : super(a, b)
+
+    constructor(n: Int) : super(n)
+
+    fun foo() {
+
+    }
+
+    fun bar() {
+
+    }
+}