Update expect

This makes writing and debugging tests so much nicer as the error
messages are a million times better, especially for nested objects.

Author: mxstbr

package.json

@@ -25,7 +25,7 @@
     "eslint-plugin-babel": "^4.1.2",
     "eslint-plugin-flowtype": "^2.35.1",
     "eslint-plugin-react": "^7.3.0",
-    "expect": "^1.20.1",
+    "expect": "^24.0.0",
     "flow-bin": "0.42.0",
     "jest": "^20.0.4",
     "lerna": "^2.1.2",