create_taxa_map(): More flexible arg specifications

[ctc3d]

It could be nice to be able to specify the output filename so successive taxa_map.csv's won't overwrite each other.

Possibly unreasonable but:
My input files come in all kinds of formats; sometimes genus and species are in separate columns. Any way to specify something like col=c('Gen', 'Spec')?

Docs quibble:
The reference page for create_taxa_map() says "Value: A .csv file named (taxa_map.csv) written to path containing the fields:..." But that's a side-effect, right? And the value is the df returned?

[clnsmth]

Thanks for these suggestions @ctc3d.

Explicitly defining inputs and outputs would definitely be an enhancement. We'll do this.

Accommodating genus and species inputs from separate columns could be supported, but would complicate updating the source data with revise_taxa(). This could probably be supported.

Since taxa_map.csv is an output from the function it has been included within the roxygen @return tag. However, I've updated the documentation (in the development branch) to list "data frame" as an output.