Only run --assemble-only when the spades assembly is not single cell
Merge pull request #243 from martinghunt/single_cell_assembly

Only run --assemble-only when the spades assembly is not single cell
Updated pseudo_genome task: requesting 2 procs and spanning 1 host.
Merge pull request #244 from fy2/pipeline

Updated pseudo_genome task: requesting 2 procs and spanning 1 host.