Write field descriptions

[dkyleward]

@gregmacfarlane would modifying the write binary.cpp to include field descriptions be terribly difficult? What are the general steps I would need to take? I really like that read_tcad brings the descriptions in as labels. I see that you are using the data.table package - does it require that the resulting DF be a data.table, or do tibbles support labels as well?

If it's involved, then this will be a long term goal. It would be nice to create the SE Data tables for our models in R and have each field fully described. For now, I can just export a CSV and copy the data into a bin table that has the right descriptions.

[gregmacfarlane]

I really don't know what would be necessary, though it would almost certainly involve the C++ code at some point.