Add function for tabular output of `taxonomy` and `taxmap` about taxa

[sckott]

Partly implemented. Works in Taxonomy objects, but will simply stop with error if variables not of the same length - Doesn't work with current ex_taxmap dataset.

Fix this in next cran push

[zachary-foster]

I think that is fine. It works if you pick vars from the same table:

ex_taxmap$get_data_frame(c("n_legs", "dangerous"))

# A tibble: 6 x 2
  n_legs dangerous
*  <dbl>     <lgl>
1      4      TRUE
2      4     FALSE
3      4     FALSE
4      2      TRUE
5      0     FALSE
6      0     FALSE

[sckott]

At least that works 😄

[zachary-foster]

Thinking about this more, I am not sure it makes sense to try to make tabular output for taxmap that includes multiple user-defined datasets, since we cant know how these data sets relate to eachother. For taxonomy, all the per-taxon data in get_data would work. For one tabular/vector dataset in a taxmap object, it could return the tabular of the taxonomy part of the object merged with the target data set.