We have started using `AsRef<Params>` in a few places as a function
parameter. If a user of the library wishes to use these functions they
need to create a type that can implement this trait. Because we use
`non_exhaustive` on the `Params` struct it is not possible to just
construct a `Params` type. This may be surprising for some folk.
Add module level docs to the `consensus::params` module with an example
of how to create a type that can be used to describe a custom signet
network. Use fields inspired by Mutiny Wallet's described usage.
Close: #2690
30a09670e8