[GSoC] Dataframes for D

[James Blachly]

On 6/3/19 11:13 PM, Prateek Nayak wrote:
> Due to the popularity of heterogeneous DataFrames, we decided to take 
> care of it the early stages of development before it's too late.
> 
> The heterogeneous DataFrame is now live at: 
> https://github.com/Kriyszig/magpie/tree/experimental

Amazing, thanks!

experimental branch readme code snippet has typo; var name should be 
`heterogeneous`

```
// Creating a heterogeneous DataFrame of 10 integer columns and 10 
double columns
DataFrame!(int, 10, double, 10) homogeneous;
```

Again I cannot thank you enough!