Update Readme file to add example for extending Format

Fix handling null in to_xml()

Apply fixes from StyleCI

Don't attempt to lowercase a NULL

Fixes PHP 8.1 deprecation notice when trying to `strtolower` `NULL`

Fix RecursiveArrayIterator not found

Update stale.yml

Merge branch 'master' of github.com:chriskacerguis/codeigniter-restse…

…rver

fix correct repo

add import to handling requests example

Bugfix/#837 add http authorization (#848)

* Bugfix
- Fix: format initialization without composer
- Fix: Readme

* Make HTTP_AUTHORIZATION possible
- To hold backward compatibility HTTP_AUTHORIZATION and HTTP_AUTHANTICATION are possible