Financial disclosure through a data-driven web page

As discussed in https://gitlab.haskell.org/hf/meta/-/merge_requests/27#note_385634, it makes a lot of sense to have budget/financials disclosure be a page (or set of pages) on our website. Since we are now properly using Hakyll, we can create a set of markdown files with summary financial information, and then generate the page(s).

I posted https://discourse.haskell.org/t/live-update-list-of-haskell-foundation-funding/2964/6 at the end of August, but the feedback was it was too detailed, so instead I could see things like:

* Per tier, per year total amounts
* Total from individual donors
* High level budget allocations and spending