Archive Zero Order Flowsheets

[MarcusHolly]

Description

All of the zero-order flowsheets were deleted in #1438, so a separate repository should be made that archives these now-deleted files.

Motivation

We still want these flowsheets to be accessible if necessary, but it's not worth the effort to constantly maintain them.

To do

• Create repository e.g. watertap-org/zero-order-flowsheets (@lbianchi-lbl)
• Figure out the most appropriate structure and a concrete list of what flowsheets should be there (@lbianchi-lbl, @MarcusHolly)

[adam-a-a]

EDIT: We decided to only remove the ZO flowsheets for now and not the units with associated docs/data. Thus the repo will be just for the flowsheets and possibly the associated yaml files for setting parameters in flowsheets.