exporting `dw_tidy` function

[IndrajeetPatil]

I am considering importing the by_2sd function from dotwhisker in my package. But, given how my function is structure, I also need to use the dw_tidy function, which is currently not exported from dotwhisker. In the next release, do you think it will be possible for you to export it?

I can't use the internal function from another package since that produces a NOTE in R CMD CHECK. Thanks.