added smple check of number of pending jobs for user. Reduced queen's worker request by number of jobs PENDing to prevent excessive queuing of workers.
added smple check of number of pending jobs for user. Reduced queen's
worker request by number of jobs PENDing to prevent excessive queuing of workers.

Ensembl/ensembl-hive,Ensembl/ensembl-hive,Ensembl/ensembl-hive,Ensembl/ensembl-hive