group codegen test files into directories per test case

idea/testData/codegen/properties/fieldPropertyAccess.jet

@@ -0,0 +1,5 @@
+private var x = 0;
+
+fun increment(): Int {
+  return ++x;
+}

idea/testData/codegen/properties/fieldSetter.jet

@@ -0,0 +1,7 @@
+var collector: String = ""
+  set(it) { $collector = $collector + it }
+
+fun append(s: String): String {
+  collector = s;
+  return collector;
+}

idea/testData/codegen/properties/fieldSetterPlusEq.jet

@@ -0,0 +1,7 @@
+var collector: String = ""
+  set(it) { $collector += it }
+
+fun append(s: String): String {
+  collector = s;
+  return collector;
+}

idea/testData/codegen/properties/privateVal.jet

@@ -0,0 +1,3 @@
+class PrivateVal() {
+  private val prop = 0;
+}

idea/testData/codegen/properties/privateVar.jet

@@ -0,0 +1,6 @@
+class PrivateVar() {
+  private var x = 0;
+
+  fun setValueOfX(aValue: Int) { x = aValue }
+  fun getValueOfX() = x
+}