add mpdf lib - add php 7.2 support - add TYPO3 9.5 support - code format

[Teisi]

Add mpdf to this repo to change this mpdf 6.1 version for support of php 7.2.

[schnere]

Thanks for your contribution! Unfortunately I don't want to have a copy of mpdf in this repository.
Please remove your .editorconfig and the mpdf lib and I'll take a look.

[Teisi]

No problem, but why you don't want a "editorconfig" file in it?
https://editorconfig.org/

Mpdf:
And the problem is that this version of mpdf is not compatible with PHP 7.2 example:
the original code at mpdf.php: "while (list($file, $info) = each($this->formobjects)) {" have to be now a foreach...
If you don't want the (modified) lib in this repo than we have to use the current mpdf version.
I think that would require much more (re-)programming.
I understand that you don't like the hole mpdf lib in your repo (not the best solution), but it is the simplest solution :)