Add donor acknowledgements

[cellio]

We are now receiving donations of both money (from people) and services (from vendors). We need a place to publicly acknowledge and thank the people who don't want to remain anonymous. We'll need to be able to update this page regularly, whether that's by direct edits or by editing a data file that the page reads dynamically. The page (I'm assuming this is a separate page) should be linked from the main landing page.

[cellio]

Page exists and is being manually updated; there's a separate effort somewhere to make updating that more straightforward than committing new versions to git, so we can close this one.