Allow passing of saveXML options (#235)

* Allow passing of saveXML options

* Feedback

Fix explicit nullable parameter for PHP 8.4 compatibility (#233)

Add proper boolean conversion to xml representation (#228)

* Add proper boolean conversion to xml representation

* Update CHANGELOG.md

* Update ArrayToXmlTest.php

Conver null based on option (#226)

* Convert null to xsi:nil based on setting

* Update ArrayToXml.php

* Update ArrayToXml.php

* Update ArrayToXmlTest__it_can_convert_an_array_with_empty_string_and_null_value_to_xml__1.xml

* Update ArrayToXml.php

Fix styling

Added Closure value support (#219)

* Added Closure value support

* Added Closure example to docs

* Changed use Closure

Add addXmlDeclaration parameter (#216)

* Add addXmlDeclaration parameter

* Add test

Backport changes from #204 (#206)

fix deprecated `passing null as string type` (#204)

Backport 3.x changes (#201)

* Backport misc changes

* Backport `Rewrite phpunit tests to pest` (#183)

This will help backporting changes from main branch

* Backport e46df26

* Backport b80f142

* Backport aaa512f

* Backport dd6f7de

* Backport 14ac461

* Backport 670ede8