update help

main.nf

@@ -34,7 +34,7 @@ def helpMessage() {
       --save_reference [bool]                   Save reference genome to output folder. Default: False
 
     Alignments
-      --split_fastq [bool]                      Size of read chuncks to use to speed up the workflow. Default: None
+      --split_fastq [int]                       Size of read chuncks to use to speed up the workflow. Default: None
       --save_aligned_intermediates [bool]       Save intermediates alignment files. Default: False 
       --bwt2_opts_end2end [str]                 Options for bowtie2 end-to-end mappinf (first mapping step). See hic.config for default.
       --bwt2_opts_trimmed [str]                 Options for bowtie2 mapping after ligation site trimming. See hic.config for default.