Upgrade to React Router v4 (#667)

* Upgrade to React Router v4

* Fix pages not change when the URL was changed.

This issue is due to the Redux `connect` wrapper around `<App/>`.
`connect` diffs changes in regular props to know when to update the
component, but doesn't check context props like `location`.
See
https://github.com/ReactTraining/react-router/blob/master/packages/react-router/docs/guides/blocked-updates.md.

* Update to new `history` methods.

package.json

@@ -72,10 +72,10 @@
     "babel-jest": "^21.2.0",
     "babel-loader": "^7.0.0",
     "babel-plugin-lodash": "^3.2.0",
+    "babel-plugin-transform-builtin-extend": "^1.1.0",
     "babel-preset-es2015": "^6.22.0",
     "babel-preset-react": "^6.23.0",
     "babel-preset-stage-1": "^6.22.0",
-    "babel-plugin-transform-builtin-extend": "^1.1.0",
     "babel-runtime": "^6.23.0",
     "cross-env": "^5.0.2",
     "css-loader": "^0.28.7",
@@ -118,7 +118,7 @@
     "fuzzy": "^0.1.1",
     "gotrue-js": "^0.9.11",
     "gray-matter": "^3.0.6",
-    "history": "^2.1.2",
+    "history": "^4.7.2",
     "immutable": "^3.7.6",
     "js-base64": "^2.1.9",
     "js-yaml": "^3.10.0",
@@ -139,8 +139,8 @@
     "react-hot-loader": "^3.0.0-beta.7",
     "react-immutable-proptypes": "^2.1.0",
     "react-redux": "^4.4.0",
-    "react-router": "^2.5.1",
-    "react-router-redux": "^4.0.5",
+    "react-router-dom": "^4.2.2",
+    "react-router-redux": "^5.0.0-alpha.6",
     "react-sidebar": "^2.2.1",
     "react-simple-dnd": "^0.1.2",
     "react-sortable": "^1.2.0",