Add a meta variable to output variable categories.

This meta-variable is specified like an array as follows, where `N` is a number and indicates the index of a group of variables for data inspection. By default, 1 represents `Local` and 2 represents `Global` (In AutoHotkey_H, 2 is `Static` and 3 is `Global`).
```
{variableCategories[N]}
```

This is useful for checking the state of a variables on the call stack at a certain point in time.