Enum parsing changed: first entries, then members. Grammar fixed accordingly.

A set of compiler tests and some plugin tests changed accordingly.
Compiler Kotlin code changed accordingly.

compiler/testData/codegen/box/enum/abstractNestedClass.kt

@@ -1,7 +1,7 @@
 enum class E {
-    abstract class Nested
-
     ENTRY
+
+    abstract class Nested
 }
 
 fun box(): String {

compiler/testData/codegen/box/secondaryConstructors/enums.kt

@@ -19,13 +19,13 @@ enum class A1(val prop1: String) {
 }
 
 enum class A2 {
-    val prop1: String
     X: A2("asd")
     Y: A2() {
         override fun f() = super.f() + "#Y"
     }
     Z: A2(5)
 
+    val prop1: String
     val prop2: String = "const2"
     var prop3: String = ""