Update Cpdf library header

Update PathTest.php for PHPunit compatibility

Render a line for a path segment with a radius of zero

fixes #97

Remove invalid condition around image href validation

Add basic protection against PHAR deserialization

This also includes an option to disable external file references. This applies to images and fonts. External file references are allowed by default, but future version will disallow by default.

Support non-namespaced href attribute

The SVG 2 specification deprecated usage of the xlink namespace when specifying resource references (href attribute) in supported SVG elements.
https://svgwg.org/svg2-draft/linking.html#XLinkRefAttrs

Do not draw indeterminite arc paths

fixes #62

Update composer configuration

- add MBString dependency
- update php-css-parser to 8.4

0.3.4

- Drop PHP support older than 7.4
- Fix PHP warning when open_basedir restriction in effect
- Correct namespace for CPdf class
- Fixed a memory leak
- Address potential offset error on null value
- Don't include tests in composer package
- Improve parsing of arc segments
- Support strokeDashoffset

Merge pull request #50 from msch-alpgis/master

Fix styles for php >= 7.0