table-style captions for code with codeBlockCaptions and labels

[nim65s]

Hello :)

As documented in README.md, this works:

a   b   c
--- --- ---
1   2   3
4   5   6

: Caption {#tbl:label}

But when I enable codeBlockCaptions, the "table-style" doesn't allow to put the label at the same place, as in:

```haskell
main :: IO ()
main = putStrLn "Hello World!"
```

: Listing caption {#lst:code}

Wouldn't it be nice ? :)

[lierdakil]

Well, that proved to be easy, so there's an implementation in master. I will hold off on release though, there's still some things I'd like to do before that. You can build from master if you want.

[nim65s]

Wow, perfect, thanks a a lot ! :D