Adding README file
Adding README file

OfficeDev/O365-PHP-Microsoft-Graph-Connect,OfficeDev/O365-PHP-Unified-API-Connect,robwilde/O365-PHP-Unified-API-Connect,robwilde/O365-PHP-Unified-API-Connect,OfficeDev/O365-PHP-Microsoft-Graph-Connect,OfficeDev/O365-PHP-Unified-API-Connect