jst_re_import() lets you re-import a file which was exported via
jst_import() or jst_import_zip().
Details
When attempting to re-import, a heuristic is applied. If the file has column
names which match the names from any of the find_* functions, the file
is read with the corresponding specifications. If no column names are
recognized, files are recognized based on the number of columns. Since both
references and footnotes have only two columns, the first line is inspected
for either "Referenc...|Bilbio...|Endnote..." or "Footnote...".
In case there is still no match, the file is read with
readr::read_csv() with guess_max = 5000 and a warning is raised.