Merge develop to master

README.md

@@ -1,15 +1,17 @@
 # Okta JWT Verifier for PHP
 
+This library helps you verify tokens that have been issued by Okta.  To learn more about verification cases and Okta's tokens please read [Working With OAuth 2.0 Tokens](https://developer.okta.com/authentication-guide/tokens/)
+
 ## Installation
 The Okta JWT Verifier can be installed through composer.
 
 ```bash
 composer require okta/jwt-verifier
 ```
 
-The library is also designed to use your favorite JWT library. We currently support 
+This library requires a JWT library. We currently support 
 [spomky-labs/jose](https://packagist.org/packages/spomky-labs/jose) and 
-[firebase/php-jwt](https://packagist.org/packages/firebase/php-jwt) You will have to install one of these or create 
+[firebase/php-jwt](https://packagist.org/packages/firebase/php-jwt). You will have to install one of these or create 
 your own adaptor.
 
 ```bash
@@ -21,7 +23,7 @@ To create your own adaptor, just implement the `Okta/JwtVerifier/Adaptors/Adapto
 You will also need to install a PSR-7 compliant library. We suggest that you use `guzzlehttp/psr7` in your project.
 
 ```bash
-composer require guzzlehttp/psr-7
+composer require guzzlehttp/psr7
 ```
 
 ## Usage
@@ -52,4 +54,4 @@ dump($jwt->getIssuedAt(false)); // returns timestamp of issued at time
 dump($jwt->getExpirationTime()); //returns Carbon instance of Expiration Time
 dump($jwt->getExpirationTime(false)); //returns timestamp of Expiration Time
 
-```
+```

composer.json

@@ -16,7 +16,7 @@
     },
     "require": {
         "php": "^7.0",
-        "symfony/yaml": "^3.2",
+        "symfony/yaml": "^3.2|^4.0",
         "nesbot/carbon": "^1.22",
         "psr/http-message": "^1.0",
         "php-http/client-common": "^1.1",