Add job_option to gem mapability function so that the no. slots asked for is the same as the number of threads specified for gem.
Add job_option to gem mapability function so that the no. slots
asked for is the same as the number of threads specified for gem.

CGATOxford/CGATPipelines,CGATOxford/CGATPipelines,AntonioJBT/CGATPipeline_core,AntonioJBT/CGATPipeline_core,CGATOxford/CGATPipelines,CGATOxford/CGATPipelines,AntonioJBT/CGATPipeline_core,CGATOxford/CGATPipelines,AntonioJBT/CGATPipeline_core