fix(react): add react-compat to deal with the warnings

React@15.5.0 introduced deprecation warnings for a few things and
they're really annoying. So this will help prevent those warnings from
logging for people using this package.

README.md

@@ -104,6 +104,9 @@ as well (if you don't already have them):
 npm install --save react glamor
 ```
 
+> NOTE: If you're using React v15.5 or greater, you'll also need to have
+> `prop-types` installed: `npm install --save prop-types`
+
 You can then use one of the module formats:
 
 - `main`: `dist/glamorous.cjs.js` - exports itself as a CommonJS module
@@ -132,6 +135,7 @@ If you want to use the global:
 ```html
 <!-- Load dependencies -->
 <script src="https://unpkg.com/react/dist/react.js"></script>
+<script src="https://packd.now.sh/prop-types?name=PropTypes"></script>
 <script src="https://unpkg.com/glamor/umd/index.js"></script>
 <!-- load library -->
 <script src="https://unpkg.com/glamorous/dist/glamorous.umd.js"></script>

package.json

@@ -57,9 +57,10 @@
     "nps-utils": "^1.1.2",
     "opt-cli": "^1.5.1",
     "prettier-eslint-cli": "^3.1.2",
-    "react": "^15.4.2",
-    "react-addons-test-utils": "^15.4.2",
-    "react-dom": "^15.4.2",
+    "prop-types": "^15.5.1",
+    "react": "^15.5.1",
+    "react-addons-test-utils": "^15.5.0",
+    "react-dom": "^15.5.1",
     "rollup": "^0.41.6",
     "rollup-plugin-babel": "^2.7.1",
     "rollup-plugin-commonjs": "^8.0.2",

rollup.config.js

@@ -18,10 +18,11 @@ export default {
   exports: 'default',
   moduleName: 'glamorous',
   format: 'umd',
-  external: ['react', 'glamor'],
+  external: ['react', 'glamor', 'prop-types'],
   globals: {
     react: 'React',
     glamor: 'Glamor',
+    'prop-types': 'PropTypes',
   },
   plugins: [
     nodeResolve({jsnext: true, main: true}),

src/index.js

@@ -6,8 +6,7 @@ import React from 'react'
 import {css, styleSheet} from 'glamor'
 import shouldForwardProperty from './should-forward-property'
 import domElements from './dom-elements'
-
-const {PropTypes} = React
+import {PropTypes} from './react-compat'
 
 /**
  * This is the main export and the function that people

src/react-compat.js

@@ -0,0 +1,14 @@
+/* eslint import/no-mutable-exports:0, import/prefer-default-export:0 */
+import React from 'react'
+
+let PropTypes
+
+/* istanbul ignore next */
+if (React.version.slice(0, 4) === '15.5') {
+  PropTypes = require('prop-types')
+  /* istanbul ignore next */
+} else {
+  PropTypes = React.PropTypes
+}
+
+export {PropTypes}