fix: use msCrypto if available. Fixes #241 (#247)

Author: broofa

lib/rng-browser.js

@@ -3,8 +3,8 @@
 // and inconsistent support for the `crypto` API.  We do the best we can via
 // feature-detection
 
-var getRandomValues = typeof(crypto) != 'undefined' && crypto.getRandomValues;
-
+var getRandomValues = (typeof(crypto) != 'undefined' && crypto.getRandomValues) ||
+                      (typeof(msCrypto) != 'undefined' && msCrypto.getRandomValues);
 if (getRandomValues) {
   // WHATWG crypto RNG - http://wiki.whatwg.org/wiki/Crypto
   var rnds8 = new Uint8Array(16); // eslint-disable-line no-undef