LIMS-67: Fix 2 slow queries on imaging admin dashboard

[ndg63276]

JIRA ticket: LIMS-67

Summary:

The imaging admin dashboard (/admin/imaging, needs privileges) is very slow to load the containers and inspections tables. This PR is to fix these slow queries, trying not to break anything else.

Changes:

• Change default sorting on container table from bltimestamp to containerid. Some sorts are still slow, but at least the default is fast now.
• Remove the join to the massive BLSampleImage table from the Inspections query, instead do that as separate smaller queries afterwards and push them into the result.
• This breaks sorting by the Scored column, but I have added the ability to sort by several other columns as compensation.

To test:

• Go to /admin/imaging, check the page loads rapidly.
• Click on one of the plates in the inspection table, check it loads up the Inspections history.
• Click on a well in the plate and add a score (eg 0 - Clear). Go back to the dashboard and check the Scored column has the value 'Yes'.
• Check sorting works on all columns in the Inspections table except Adhoc, Manual and Scored.
• Choose Containers from the main menu, check the containers list loads ok.