Refactor the balances module (#4649)

* Initially scoping out of the problem

* Remove need for exiry in balance locks.

* Remove expiry from locks.

* Remove supefluous balance test

* Amalgamate pieces of balance module

* Split out vesting

* Fix tests

* Fixes for vesting.

* Docs.

* Weight docs.

* Refactor things in terms of set_balances.

* Switch out ED to be free + reserved.

* Remove on_free_balance_zero and some docs.

* Build fixes

* Update frame/vesting/src/lib.rs

Co-Authored-By: Xiliang Chen <xlchen1291@gmail.com>

* Update frame/vesting/src/lib.rs

Co-Authored-By: Xiliang Chen <xlchen1291@gmail.com>

* Migration

* Remove superfluous code.

* Test fixes

* Fix some tests

* Fix repatriate reserve

* Fixes

* Add test for migration

* Final cleanups

* Fix

* Indentation.

* Undo unneeded referencing

* Bump runtime version

* Fixes

Co-authored-by: Xiliang Chen <xlchen1291@gmail.com>

substrate/frame/utility/src/lib.rs

@@ -703,19 +703,16 @@ mod tests {
 	}
 	parameter_types! {
 		pub const ExistentialDeposit: u64 = 0;
-		pub const TransferFee: u64 = 0;
 		pub const CreationFee: u64 = 0;
 	}
 	impl pallet_balances::Trait for Test {
 		type Balance = u64;
-		type OnFreeBalanceZero = ();
 		type OnReapAccount = System;
 		type OnNewAccount = ();
 		type Event = TestEvent;
 		type TransferPayment = ();
 		type DustRemoval = ();
 		type ExistentialDeposit = ExistentialDeposit;
-		type TransferFee = TransferFee;
 		type CreationFee = CreationFee;
 	}
 	parameter_types! {
@@ -742,7 +739,6 @@ mod tests {
 		let mut t = frame_system::GenesisConfig::default().build_storage::<Test>().unwrap();
 		pallet_balances::GenesisConfig::<Test> {
 			balances: vec![(1, 10), (2, 10), (3, 10), (4, 10), (5, 10)],
-			vesting: vec![],
 		}.assimilate_storage(&mut t).unwrap();
 		t.into()
 	}