switch usages of npm run react

CONTRIBUTING.md

@@ -18,30 +18,37 @@ git clone https://github.com/airbnb/enzyme.git
 cd enzyme
 
 # install dependencies (use react:13 if you want to use React 0.13)
-npm install && npm run react:14
+npm install && npm run react 14
 ```
 
 
-### Switching between React 15, React 0.14 and React 0.13
+### Switching between React 16, React 15, React 0.14 and React 0.13
 
 ```bash
 # switch to React 0.13
-npm run react:13
+npm run react 13
 ```
 
 ```bash
 # switch to React 0.14
-npm run react:14
+npm run react 14
 ```
 
 ```bash
 # switch to React 15
-npm run react:15
+npm run react 15
 ```
 
 ```bash
 # switch to React 16
-npm run react:16
+npm run react 16
+```
+
+Specific versions can also be specified
+
+```bash
+# switch to React 16.5
+npm run react 16.5
 ```
 
 ### Running Tests

package.json

@@ -27,8 +27,7 @@
     "test:watch": "mocha --recursive --watch packages/enzyme-test-suite/test",
     "pretest:karma": "npm run build",
     "test:karma": "karma start",
-    "test:env": "sh ./example-test.sh",
-    "test:all": "npm run react:13 && npm run test:only && npm run react:14 && npm run test:only && npm run react:15.4 && npm run test:only && npm run react:15 && npm run test:only && npm run react:16.1 && npm run test:only && npm run react:16.2 && npm run test:only && npm run react:16.3 && npm run test:only && npm run react:16 && npm run test:only",
+    "test:all": "npm run react 13 && npm run test:only && npm run react 14 && npm run test:only && npm run react 15 && npm run test:only && npm run react 15.4 && npm run test:only && npm run react 15.5 && npm run test:only && npm run react 16 && npm run test:only && npm run react 16.1 && npm run test:only && npm run react 16.2 && npm run test:only && npm run react 16.3 && npm run test:only && npm run react 16.4 && npm run test:only && npm run react 16.5 && npm run test:only",
     "react": "sh install-relevant-react.sh",
     "env": "babel-node ./env.js",
     "docs:clean": "rimraf _book",