title: Encrypt a string in PHP where the output is URL safe
body: <p>I have a requirement where I need to move a string from one place to another via GET. e.g. 
  example.com?string=ENCRYPTED_STRING</p>
  
  <p>Is there a algorithm or some other method to encrypt the string so it is URL safe?</p>
  
  <p>By that I mean it will not have characters like = or &amp; ...</p>
  
  <p>I have tried openssl with AES-256-CBC but no luck.</p>
  
  <p>The data is not overly very sensitive but I would prefer to obfuscate it in someway.</p>