3605: Additional layout fixes.  Better handling of pipelines where started_at and finished_at is missing or bogus.
3605: Change runtime() to render_runtime().  Improve rendering when started_at
and finished_at are missing from pipelines and tasks.  Include count of days
when rendering run times.  Add comments.
3605: More improvements to overflow rendering.  More fixes to rendering when
started_at and finished_at are missing.
3605: Render individual job status using the same partial as the pipeline
instance page.  Also list pipelines that reference this job.
3605: Make compute node summary table no longer clickable since it was a little
bit confusing.  Can still click on the titlebar.
3605: fix test text
3605: Check that a pipeline component entry is a hash before trying to render it.
3605: Fallback to 0 (instead of nil) when tasks is empty
3605: Filter out nodes that have a last ping time of more than 1 hour.  Add
queue to compute status panel.  Refactor utc-date spans to
render_localized_date().
3605: Rename "default_show" to "title_and_buttons".  Revert capitalization
change to "curl".  Eliminate excess top margin on page title.  Restored
RunningOnClient to running list.
Merge remote-tracking branch 'origin/master' into 3605-improved-dashboard
3605: Remove total nodes from compute summary table.
Merge branch '3605-improved-dashboard' refs #3605