swim_parseTakes the output of read_results and, inside of swim_parse,
extracts split times and associated row numbers
splits_parse(text, split_len = split_length)returns a data frame with split times and row numbers
output of read_results with row numbers appended by
add_row_numbers
length of pool at which splits are measured - usually 25 or 50
splits_parse runs inside swim_parse on the
output of read_results with row numbers from
add_row_numbers