memberof does not cascade down to class members

With the following code:

```
/** @module module */

/**
* @class Clazz
* @memberof module
*/
class Clazz {
/** Whatever */
member = 7
}
```

The `member` member gets documented as a root-level item with `"memberof": "Clazz",`. It really should be a memberof `module.Clazz`. Adding an explicit `memberof` does allow it to generate the correct docs. This is possibly related to #417 but seems to be more an extension of the same problem. (I already think there's an open issue that @module should already imply that `Clazz` is a `memberof` `module`. If not, I'll be happy to create one)