Bugfix: Don't crash trying to render a new log buffer.

If you submit a Job and then try to load your Workbench Dashboard,
Workbench will likely crash because the log_buffer is a symbol at that
time.  This check guards to make sure that we only try to render
actual log content.
2739: Ensure crunch-job spawns all new tasks.

Without this fix, crunch-job would only spawn tasks up to the API
server default result limit (currently 100).  Refs #2739.
Merge branch '2739-fix-100-task-limit-wip'

Closes #2739.