updated gunzip to force overwrite if file already exists
updated gunzip to force overwrite if file already exists

cjprybol/Neurospora_BSA_mutation_mapper,cjprybol/Neurospora_BSA_mutation_mapper,cprybol/Neurospora_BSA_mutation_mapper,cprybol/Neurospora_BSA_mutation_mapper,cjprybol/Neurospora_BSA_mutation_mapper,cprybol/Neurospora_BSA_mutation_mapper