Change HS256 to HS512, and remove json example

Author: BaseMax

encode.php

@@ -7,18 +7,5 @@
 
 // plain text
 $data = "Hello, World!";
-$jwt = JWT::encode($data, $key, 'HS256');
-print $jwt."\n";
-
-// JSON
-$data=[
-  "status"=>"success",
-  "data1"=>"test1",
-  "data2"=>"test2",
-  "data3"=>"test3",
-  "data4"=>"test4",
-  "data5"=>"test5",
-];
-$data = json_encode($data);
-$jwt = JWT::encode($data, $key, 'HS256');
+$jwt = JWT::encode($data, $key, 'HS512');
 print $jwt."\n";