Added "ignore_barcodes_for_de_novo" option to config file
	this option will allow to either run denovo assembly on all barcodes individually, or assemble all barcodes together
Adjusted assembly to allow for input file with no barcodes - will assemble everything into a single assembly
Adjusted preprocessing to lower space usage a bit
Added ribosomal cleanup step for nonchordateuk
Merge branch 'master' of https://github.com/chiulab/surpi