Add kovan config settings to config manager.

app/scripts/lib/config-manager.js

@@ -5,6 +5,7 @@ const normalize = require('eth-sig-util').normalize
 const TESTNET_RPC = MetamaskConfig.network.testnet
 const MAINNET_RPC = MetamaskConfig.network.mainnet
 const MORDEN_RPC = MetamaskConfig.network.morden
+const KOVAN_RPC = MetamaskConfig.network.kovan
 
 /* The config-manager is a convenience object
  * wrapping a pojo-migrator.
@@ -150,6 +151,9 @@ ConfigManager.prototype.getCurrentRpcAddress = function () {
     case 'morden':
       return MORDEN_RPC
 
+    case 'kovan':
+      return KOVAN_RPC
+
     default:
       return provider && provider.rpcTarget ? provider.rpcTarget : TESTNET_RPC
   }