Unrecognized loop range type: list of integers (new feature)

Hi,

I am trying to use ```@turbo``` to loop over a list of integers. Naive implementations such as
```julia
@turbo for i in [1,10,15]
# do something
end
```

do not seem to work. However, simple workarounds like
```julia
ind = [1,10,15];
@turbo for j in eachindex(ind)
i = ind[j]
# do something
end
```

work fine. Is there any chance that similar cases will be handled as in the first example (i.e., naive implementation) in future releases?

Start at the @turbo loop handling, using the direct list-of-integers example and the eachindex workaround as behavioral references. Done means the direct list-of-integers form is accepted with equivalent loop behavior, with coverage demonstrating that case.

索引モデルが issue の本文から書いたものです。