Merge rust-bitcoin#4658: backport to v0.32: Remove non_exhaustive from Network

3cf4a91 Remove non_exhausive from Network (Tobin C. Harding)

Pull request description:

  This is rust-bitcoin#4640 backported manually. Remove `non_exhaustive` from `Network` enum.


ACKs for top commit:
  apoelstra:
    ACK 3cf4a91; successfully ran local tests


Tree-SHA512: 690cdcf82a9e87f2100aa8e996583bd54f969d8d55eba062ace66bdf2ae9ae1c482d6220bb26690ebfaf3a35ca3f5ce0ecaac3a79b4061c75e9fb7adbe032f48

Author: apoelstra

bitcoin/src/network.rs

@@ -59,11 +59,19 @@ impl From<Network> for NetworkKind {
 }
 
 /// The cryptocurrency network to act on.
+///
+/// This is an exhaustive enum, meaning that we cannot add any future networks without defining a
+/// new, incompatible version of this type. If you are using this type directly and wish to support the
+/// new network, this will be a breaking change to your APIs and likely require changes in your code.
+///
+/// If you are concerned about forward compatibility, consider using `T: Into<Params>` instead of
+/// this type as a parameter to functions in your public API, or directly using the `Params` type.
+// For extensive discussion on the usage of `non_exhaustive` please see:
+// https://github.com/rust-bitcoin/rust-bitcoin/issues/2225
 #[derive(Copy, PartialEq, Eq, PartialOrd, Ord, Clone, Hash, Debug)]
 #[cfg_attr(feature = "serde", derive(Serialize, Deserialize))]
 #[cfg_attr(feature = "serde", serde(crate = "actual_serde"))]
 #[cfg_attr(feature = "serde", serde(rename_all = "lowercase"))]
-#[non_exhaustive]
 pub enum Network {
     /// Mainnet Bitcoin.
     Bitcoin,