Merge pull request #49 from Bandwidth/task/fix-supported-version

Update supported PHP Version in README and `composer.json`

Author: ajrice6713

README.md

@@ -141,7 +141,7 @@ $webRtcClient->addParticipantToSession($accountId, $sessionId, $participantId);
 
 ## Supported PHP Versions
 
-This package can be used with PHP >= 5.4
+This package can be used with PHP >= 7.2
 
 ## Documentation
 

composer.json

@@ -15,7 +15,7 @@
     ],
     "require": {
         "ext-SimpleXML": "*",
-        "php": ">=5.4.0",
+        "php": ">=7.2.0",
         "ext-curl": "*",
         "ext-json": "*",
         "ext-mbstring": "*",