PrivateKey: Fixed documentation

docs/PrivateKey.md

@@ -21,7 +21,7 @@ To export and import a private key, you can do the following:
 var exported = privateKey.toWIF();
 
 // instantiate from the exported (and saved) private key
-var imported = PrivateKey.fromWIF(exported);
+var imported = PrivateKey.fromWIF('L3T1s1TYP9oyhHpXgkyLoJFGniEgkv2Jhi138d7R2yJ9F4QdDU2m');
 
 ```
 
@@ -52,6 +52,5 @@ var error = PrivateKey.getValidationError(input, Networks.livenet);
 if (error) {
   // handle the error
 }
-}
 
 ```

lib/privatekey.js

@@ -103,7 +103,7 @@ var PrivateKey = function PrivateKey(data, network, compressed) {
 /**
  * Internal function to get a random BN
  *
- * @returns {BN} An object with keys: bn, network and compressed
+ * @returns {BN} A new randomly generated BN
  * @private
  */
 PrivateKey._getRandomBN = function(){