Line around charts should be removed

[rf1234]

This is:

- [ ] a bug report
- [x ] a feature request
- [ ] **not** a usage question (ask them on https://stackoverflow.com/questions/tagged/phpspreadsheet or https://gitter.im/PHPOffice/PhpSpreadsheet)

What is the expected behavior

charts shouldn't have a line around them. This looks ugly and also unprofessional. It should be possible to remove the line or to never have a line around a chart:

What is the current behavior?

The line cannot be removed. I use a hard coded solution to get rid of it.

What are the steps to reproduce?

This is my hard coded fix in "Chart.php" in the "Xlsx" folder starting line 101 right before
$this->writePrintSettings($objWriter);

<?php
//Roland Finke: Remove shape outline of chart
        $objWriter->startElement('c:spPr');
            $objWriter->startElement('a:ln');
                $objWriter->startElement('a:noFill');
                $objWriter->endElement();
            $objWriter->endElement();
        $objWriter->endElement();
        //Roland Finke: end

Which versions of PhpSpreadsheet and PHP are affected?

[stale]

This issue has been automatically marked as stale because it has not had recent activity. It will be closed if no further activity occurs.
If this is still an issue for you, please try to help by debugging it further and sharing your results.
Thank you for your contributions.

[oleibman]

Easily accomplished, reopening.