refactor: Transaction-Payment module (#3816)

* Initial draft that compiles

* Extract payment stuff from balances

* Extract multiplier update stuff from system

* Some fixes.

* Update len-fee as well

* some review comments.

* Remove todo

* bump

substrate/node/testing/Cargo.toml

@@ -27,4 +27,5 @@ system = { package = "srml-system", path = "../../srml/system" }
 test-client = { package = "substrate-test-client", path = "../../core/test-client" }
 timestamp = { package = "srml-timestamp", path = "../../srml/timestamp" }
 treasury = { package = "srml-treasury", path = "../../srml/treasury" }
+transaction-payment = { package = "srml-transaction-payment", path = "../../srml/transaction-payment" }
 wabt = "0.9.2"

substrate/node/testing/src/keyring.rs

@@ -72,7 +72,7 @@ pub fn signed_extra(nonce: Index, extra_fee: Balance) -> SignedExtra {
 		system::CheckEra::from(Era::mortal(256, 0)),
 		system::CheckNonce::from(nonce),
 		system::CheckWeight::new(),
-		balances::TakeFees::from(extra_fee),
+		transaction_payment::ChargeTransactionPayment::from(extra_fee),
 		Default::default(),
 	)
 }