[GNC] New CSV Import Wiki Entries

[flywire]

probably best to start with the Wiki, where I edits are easy. Also
others can improve on my Wiki work.

I agree. Good to see CSV import docs contributions.

https://wiki.gnucash.org/wiki/Documentation_Improvement ... is more
akin to code development.

Personally, I think the community would benefit from replacing the
documentation system with a markdown based system making it much
easier for community contributions.

Regards