Revert 2238768be3 changes to this file only

Commit 2238768be3 made several changes. The ones to this file meant that when cliking the "Edit the published programme" link, we got 'Fatal error: Cannot use object of type stdClass as array in /home/spaconfer/public_html/private_scripts/db_proposal.php on line 144'. Reverting this file only fixes the problem.