Sort::SQL is so simple it almost doesn't deserve to be on CPAN. But since I kept
finding myself copy/pasting this method into multiple places, I finally figured
it deserved to live in its own class.

Sort::SQL implements one method: string2array().

Takes a scalar string of the SQL C<ORDER BY> syntax and turns it into
an array of key/value pair hashrefs.

This method can be used e.g. in Template Toolkit applications, to create
re-sortable table columns.