`get_records = 'both'` is not implemented

[jpeacock29]

Again, apologies if I'm missing something, but get_refs function does not appear to implement this functionality. For example, the following code returns NULL:

get_refs(c("10.1111/sum.12030"), save_object=TRUE, type = "doi", get_records="both",
token="XXX")

Furthermore, searching the code, I saw conditional branches for "references" and "citations", but "both" doesn't seem to be handled anywhere.