Add an initial Substrate instantiation

Consensus has been nuked for an AcceptAny currently routed throough PoW 
(when it doesn't have to be, doing so just took care of a few pieces of 
leg work).

Updates AGPL handling.

substrate/node/src/chain_spec.rs

@@ -0,0 +1,74 @@
+use sc_service::ChainType;
+
+use sp_runtime::traits::Verify;
+use sp_core::{sr25519, Pair, Public};
+
+use sp_runtime::traits::IdentifyAccount;
+
+use serai_runtime::{
+  WASM_BINARY, AccountId, Signature, GenesisConfig, SystemConfig, BalancesConfig
+};
+
+pub type ChainSpec = sc_service::GenericChainSpec<GenesisConfig>;
+type AccountPublic = <Signature as Verify>::Signer;
+
+fn get_from_seed<TPublic: Public>(seed: &'static str) -> <TPublic::Pair as Pair>::Public {
+  TPublic::Pair::from_string(&format!("//{}", seed), None).unwrap().public()
+}
+
+fn get_account_id_from_seed<TPublic: Public>(seed: &'static str) -> AccountId
+  where AccountPublic: From<<TPublic::Pair as Pair>::Public> {
+  AccountPublic::from(get_from_seed::<TPublic>(seed)).into_account()
+}
+
+fn testnet_genesis(
+  wasm_binary: &[u8],
+  endowed_accounts: Vec<AccountId>
+) -> GenesisConfig {
+  GenesisConfig {
+    system: SystemConfig {
+      code: wasm_binary.to_vec(),
+    },
+    balances: BalancesConfig {
+      balances: endowed_accounts.iter().cloned().map(|k| (k, 1 << 60)).collect(),
+    },
+    transaction_payment: Default::default()
+  }
+}
+
+pub fn development_config() -> Result<ChainSpec, &'static str> {
+  let wasm_binary = WASM_BINARY.ok_or_else(|| "Development wasm not available")?;
+
+  Ok(
+    ChainSpec::from_genesis(
+      // Name
+      "Development Network",
+      // ID
+      "dev",
+      ChainType::Development,
+      || {
+        testnet_genesis(
+          wasm_binary,
+          vec![
+            get_account_id_from_seed::<sr25519::Public>("Alice"),
+            get_account_id_from_seed::<sr25519::Public>("Bob"),
+            get_account_id_from_seed::<sr25519::Public>("Alice//stash"),
+            get_account_id_from_seed::<sr25519::Public>("Bob//stash"),
+          ]
+        )
+      },
+      // Bootnodes
+      vec![],
+      // Telemetry
+      None,
+      // Protocol ID
+      Some("serai"),
+      // Fork ID
+      None,
+      // Properties
+      None,
+      // Extensions
+      None
+    )
+  )
+}