Cascade from _index.md

[tyco]

@jmooring

Or to put it another way, why would you need hundreds of cascade tables?

Like in the link post shared, somehow a decision was made at a place I volunteer to group together some content and I presented the multipage posts solution you shared in another post. However, they wanted again to break that content down like in the linked forum post so that similar content share different titles across different folders in the multipage bundle. I tried that trick and it worked, but when we are talking about more than one multilingual posts, those cascades will add up. Hence my concern about cluttering the hugo.toml at root (and back to my first post about using _index.md to cascade instead).