setting property plotVisOnly for charts
*Created originally on Bitbucket by [matt_lie (Matthias Lienert)](https://bitbucket.org/%7B6e62dc63-bbf1-4801-996e-4f4e5f35e9b4%7D/)*
I tried to set/unset the option for plotting hided lines in charts.
The entry in the xlsx -> chart.xml is plotVisOnly
Is there a generic way to set properties in excel which are not natively suported in openpyxl? or is there a "real" method or attribute to manipulate the plotVisOnly option?
In the "excel-GUI" the option can be found in context menu of a chart -> select data.... -> Hided and empty cells -> show data in hided rows and cols
issue