core, subkey: allow to read Polkadot, Kusama, and Dothereum address types (#3643)

* core/primitives: set dothereum address type to 4

* subkey: add dothereum to network prefix

* core/primitives: set dothereum address type to 20

* core/primitives: update comment

* core/primitives: set default address to Dothereum

* Revert "core/primitives: set default address to Dothereum"

This reverts commit 2fc95490c89390eb26f200cb314435b1e9ff83e8.

* core/primitives: allow to parse different default address types

substrate/subkey/src/cli.yml

@@ -23,7 +23,7 @@ args:
       long: network
       takes_value: true
       required: false
-      help: Specify a network. One of substrate (default), polkadot and kusama.
+      help: Specify a network. One of substrate (default), polkadot, kusama, or dothereum.
 subcommands:
   - generate:
       about: Generate a random account

substrate/subkey/src/main.rs

@@ -140,7 +140,7 @@ where
 	let maybe_network: Option<Ss58AddressFormat> = matches.value_of("network").map(|network| {
 		network
 			.try_into()
-			.expect("Invalid network name: must be polkadot/substrate/kusama")
+			.expect("Invalid network name: must be polkadot/substrate/kusama/dothereum")
 	});
 	if let Some(network) = maybe_network {
 		set_default_ss58_version(network);
@@ -382,7 +382,7 @@ fn create_extrinsic(
 	);
 	let signature = raw_payload.using_encoded(|payload| signer.sign(payload));
 	let (function, extra, _) = raw_payload.deconstruct();
-	
+
 	UncheckedExtrinsic::new_signed(
 		function,
 		signer.public().into(),