[JES] Update schema to update the creation of an index (currently partial but...

[JES] Update schema to update the creation of an index (currently partial but we decided we'd prefer to have the full index since many posts are not 'deleted'); add comments to sql queries to aid in tracking down slow ones from interfaces like pghero (queries get truncated and it's not obvious which one pghero is referring to, but a comment at the beginning of the query will always be displayed so there's no guessing)