CSV multi series export

[Redirts]

Is your feature request related to a problem? Please describe.
CSV export

Describe the solution you'd like
When exporting CSV on a chart with multi series, all the series are written sequentially
It would be nice to have the series values appear in a separate column.

Also date column should be formatted to a readable date format if possible.

Additional context
Currently:

Desired:

if no value exists for the x value then it should be left blank

[junedchhipa]

Thanks for the suggestion. Implemented it, will be available in the next patch release.