Created module idea-test-framework and moved classes needed for idea tests there

Moved tests for completion and their test data into module idea-completion

idea/idea-completion/testData/basic/common/InSecondaryConstructorBody.kt

@@ -0,0 +1,14 @@
+fun topLevel() = 1
+
+class A(val prop: Int, arg: Int) {
+    val another = 1
+    constructor(abc: Int): this(1, 2) {
+        val local = 1
+        <caret>
+    }
+
+    fun foo() = 1
+}
+
+// EXIST: prop, abc, another, foo, local, topLevel
+// ABSENT: arg