Fix the stop time for the temperature plot on "historic" weeks.

starcheck.calc_ccd_temps is set to just plot telemetry values instead
of calculating the model for older data.  The recent cmd_states change
changed the stop time for the telemetry fetching to 2099:001 .  This was
only visible in the plots and did not show up in the regression tests.
Add acq/gui stat lookup links to all agasc ids if no database connection

The starcheck text said that we were doing this:

Unable to connect to Sybase server; links generated for all AGASC ids by default

but the code to do it wasn't actually present.  Useful on GRETA.
Plot the ccd temp limit lines before the obsid markers

For old data with limited range, the distance between the limit lines
dominates the scale and that isn't reflected in the marker placement if
the obsid markers are done first.
Scale CCD temperature plots more reasonably

Consider the limit lines as "data" for the purposes of the plot so they
are always included within the Y limits.
Add grey background to CCD temp plot

Add grey background to CCD temp plot for the time ranges outside the
time range in review in the current backstop used for starcheck.

Also remove blue vertical line at load start as no longer needed.