Ensure compatibility for both react-router v1 and v2

- Add fallback for react-router@1:
  - `history@1` used to be separately installed and instantiated
  - `RouterContext` used to be named `RoutingContext`

Author: remarkablemark

lib/client.js

@@ -57,7 +57,9 @@ exports.boot = function boot(options, callback) {
     Router = require('react-router');
     RouterComponent = Router.Router;
     match = Router.match;
-    browserHistory = Router.browserHistory;
+
+    // compatibility for both `react-router` v2 and v1
+    browserHistory = Router.browserHistory || require('history').createHistory();
   } catch (err) {
     if (!Router && options.routes) {
       throw err;

lib/server.js

@@ -61,7 +61,9 @@ exports.create = function create(createOptions) {
   try {
     Router = require('react-router');
     match = Router.match;
-    RouterContext = Router.RouterContext;
+
+    // compatibility for both `react-router` v2 and v1
+    RouterContext = Router.RouterContext || Router.RoutingContext;
   } catch (err) {
     if (!Router && createOptions.routes) {
       throw err;