v3.0.1

Fixed

• No more curl_close() is deprecated notices on PHP 8.5. The client no longer calls curl_close(),
  which has done nothing since PHP 8.0; cURL handles are freed when they go out of scope.
• ResultFile::getContents() is documented as returning false|string, as file_get_contents() does
  (#65).

Changed

• ConvertApi::VERSION, sent in the User-Agent, is 3.0.1.
• Added examples/vanilla_php.php, a conversion with plain PHP cURL and no client library.
• The default branch is main (was master). Composer users requiring dev-master should require
  dev-main or a tagged version.
• Releases are now cut from a GitHub Release v{version} on main, checked by release.yml. Every pull
  request is built on PHP 8.1, 8.2, 8.3, 8.4 and 8.5.

Full Changelog: v3.0.0...v3.0.1