Add a list of Mastodon servers to README.MD that uses Hometown

[expertmanofficial]

Pitch

Title says it all, but for more context, Mastodon is too much expensive for me to run, so, I would like to try Hometown.

Motivation

It would be easier to see what is it like to use Hometown.

[rscmbbng]

Such a list can be found in the wiki: https://github.com/hometown-fork/hometown/wiki/Hometown-servers

However, regarding expenses, hometown is basically 99.5% Mastodon (the .5% difference) so you are unlikely to experience a very different situation.

[technicat]

FediDB is also a good resource

https://fedidb.org/software/hometown