Nextflow process cannot access orthogroup snp data stored in NemaScanDir

[mckeowr1]

The process simulate_orthogroup_effects runs a python script sim_og_effects.py that script loads variants from a master_snps_file that has all SNPs > 1% maf annotated with OGIDs. The script has the relative paths (`test_data/-master.snps.genes) to these input files are hard coded but NemaScan is unable to find them.

Short term fix:
Need to add a Parameter to multi_species_simfiles.nf for the data dir and put SNPs there. I can pass the data dir as a command line argument to sim_og_effects.py

Long term fix:
Add the master snps file to the pipeline workflow. This would have to take place during sim file prep, probably when VCFs and indexs are defined for each strain set.