Service various cleanups (#3238)

* Remove generic from sign()

* Remove mandatory RuntimeGenesis trait req

* Remove requirement from Configuration

* Relax trait bounds of core/cli

* Move method

* The config field is no longer public

* Remove Components from bounds of functions

* Implement DerefMut for LightComponents

* Implement Executor for Full/LightComponents

* Fix bad merge

* Fix forgotten config()

* Fix build

substrate/node-template/src/service.rs

@@ -83,8 +83,8 @@ construct_service_factory! {
 						client,
 						proposer,
 						service.network(),
-						service.config.custom.inherent_data_providers.clone(),
-						service.config.force_authoring,
+						service.config().custom.inherent_data_providers.clone(),
+						service.config().force_authoring,
 					)?;
 					service.spawn_task(Box::new(aura.select(service.on_exit()).then(|_| Ok(()))));
 				}