Release 120

This release includes for proxy as
Ticket for iteration 5;
Fix #155
Fix #195
Fix #196
Fix #217
Fix #218

Author: tlacloc

runtime/src/lib.rs

@@ -106,7 +106,7 @@ pub const VERSION: RuntimeVersion = RuntimeVersion {
 	//   `spec_version`, and `authoring_version` are the same between Wasm and native.
 	// This value is set to 100 to notify Polkadot-JS App (https://polkadot.js.org/apps) to use
 	//   the compatible custom types.
-	spec_version: 119,
+	spec_version: 120,
 	impl_version: 1,
 	apis: RUNTIME_API_VERSIONS,
 	transaction_version: 1,