Introduce safe types for handling imbalances (#2048)

* Be a little safer with total issuance.

* PairT instead of _Pair

* Remove rev causing upset

* Remove fees stuff.

* Fix build (including tests)

* Update runtime, bump version

* Fix

* Handle gas refunds properly.

* Rename identifier

ala #2025

* Address grumbles

* New not-quite-linear-typing API

* Slimmer API

* More linear-type test fixes

* Fix tests

* Tidy

* Fix some grumbles

* Keep unchecked functions private

* Remove another less-than-safe currency function and ensure that
contracts module can never create cash.

* Address a few grumbles and fix tests

substrate/node-template/src/chain_spec.rs

@@ -1,7 +1,7 @@
 use primitives::{ed25519, Pair};
 use node_template_runtime::{
 	AccountId, GenesisConfig, ConsensusConfig, TimestampConfig, BalancesConfig,
-	SudoConfig, IndicesConfig, FeesConfig,
+	SudoConfig, IndicesConfig,
 };
 use substrate_service;
 
@@ -104,6 +104,8 @@ fn testnet_genesis(initial_authorities: Vec<AuthorityId>, endowed_accounts: Vec<
 			ids: endowed_accounts.clone(),
 		}),
 		balances: Some(BalancesConfig {
+			transaction_base_fee: 1,
+			transaction_byte_fee: 0,
 			existential_deposit: 500,
 			transfer_fee: 0,
 			creation_fee: 0,
@@ -113,9 +115,5 @@ fn testnet_genesis(initial_authorities: Vec<AuthorityId>, endowed_accounts: Vec<
 		sudo: Some(SudoConfig {
 			key: root_key,
 		}),
-		fees: Some(FeesConfig {
-			transaction_base_fee: 1,
-			transaction_byte_fee: 0,
-		})
 	}
 }

substrate/node-template/src/service.rs

@@ -15,7 +15,7 @@ use basic_authorship::ProposerFactory;
 use node_executor;
 use consensus::{import_queue, start_aura, AuraImportQueue, SlotDuration, NothingExtra};
 use substrate_client as client;
-use primitives::{ed25519::Pair, Pair as _Pair};
+use primitives::{ed25519::Pair, Pair as PairT};
 use inherents::InherentDataProviders;
 use network::construct_simple_protocol;
 use substrate_executor::native_executor_instance;