config: move common part of notary/state into InternalService

pkg/config/internal_service.go

@@ -0,0 +1,8 @@
+package config
+
+// InternalService stores configuration for internal services that don't have
+// any network configuration, but use a wallet and can be enabled/disabled.
+type InternalService struct {
+	Enabled      bool   `yaml:"Enabled"`
+	UnlockWallet Wallet `yaml:"UnlockWallet"`
+}

pkg/config/notary_config.go

@@ -1,7 +1,4 @@
 package config
 
 // P2PNotary stores configuration for Notary node service.
-type P2PNotary struct {
+type P2PNotary InternalService
-	Enabled      bool   `yaml:"Enabled"`
-	UnlockWallet Wallet `yaml:"UnlockWallet"`
-}

pkg/config/state_root.go

@@ -1,7 +1,4 @@
 package config
 
 // StateRoot contains state root service configuration.
-type StateRoot struct {
+type StateRoot InternalService
-	Enabled      bool   `yaml:"Enabled"`
-	UnlockWallet Wallet `yaml:"UnlockWallet"`
-}