meta tag causes stdout (warning?) codo_free fail 21 0
My apologies if this is not a bug, I have no idea how the `__meta:*__` tag works or what it does, and can't find any documentation on it other than it being briefly mentioned in the 0.2.4 changelog. 

Shrinko8 appends this line to the end of the cart when minified:
```
__meta:title__
>8
```

Those lines' presence in the cart causes Pico-8 to print this message to stdout in a Linux shell (not stdout, though I'm not sure if Pico-8 would differentiate between the two). 

```
codo_free fail 21 0
```

It seems like some kind of warning message?

Anyway, thanks for making this great new tool! 