Augment the date/time examples in the User's Guide to reflect the newer

Augment the date/time examples in the User's Guide to reflect the newer
 capabilities of specifying time zones as intervals per SQL9x.
Put refentrytitle contents on the same line as the tag.
 Otherwise, leading whitespace is propagated into the product, which
 (at least) messes up the ToC layout.
Remove (some) docinfo tags containing dates. Best to omit if the dates
 are not accurate; maybe use CVS dates instead or leave them out.