Added automatic distructor calling for going out of scope, found out that += is broken (and just comes through as =)

tests/to_parse.krak

@@ -17,8 +17,8 @@ obj Something (ObjectTrait) {
         member = old->member
     }
     fun destruct() {
-        simple_println("Destructing a Something")
-        member = -800
+        simple_print("Destructing a Something: ")
+        simple_println(member)
     }
     fun method(a: int):int {
         return 5+a+member + other_method()
@@ -107,6 +107,7 @@ fun main(): int {
     simple_println(test_methods.member)
     simple_println(test_methods_param.member)
     var second_obj = test_methods
+    second_obj.member += 5
     simple_println(second_obj.member)
     return 0
 }