Functions for working with the high performance computing cluster
hpcc_get_arg() retrieve character argument passed from terminal,
e.g. qsubR bootstrap_analysis.R "mets"
hpcc_get_seq_number() retrieve sequence integer when a sequence of jobs
were submitted from the terminal, e.g qsubR -a 1-50%10 bootstrap_analysis.R
hpcc_get_arg()
hpcc_get_seq_number()