Track graphics hardware in agents
Try to fix tests
Fix celery tasks

We need to import the GPU class once so that sqlalchemy can properly set
up its internal data structures
Fix typo in environment var name
Fix docstring for module (minor)
Retain job order and filters on rerunning a job
Fix infinite loop in task_delete

We are done with this loop even if we did not have to delete the job.
Only InvalidRequestErrors should make us repeat.
Show icon for jobs blocked by a dependency
Allow upgrading jobs to latest jobtype version
Import INTERNAL_SERVER_ERROR
Merge pull request #306 from guidow/track_agent_gpus

Track graphics hardware in agents
Merge pull request #307 from guidow/retain_order_filter_on_rerun

Retain job order and filters on rerunning a job
Merge pull request #308 from guidow/fix_infinite_loop_in_task_delete

Fix infinite loop in task_delete
Merge pull request #309 from guidow/icon_for_blocked_jobs

Show icon for jobs blocked by a dependency
Merge pull request #310 from guidow/upgrade_jobtype_version_ui

Allow upgrading jobs to latest jobtype version