Changes for zSQLgate, version 1.02

Changes between versions 1.01 and 1.02 (Fri May 2 17:23:49 2008):

• Use left joins for auxiliary tables, so that missing values in the auxiliary tables don't prevent data in the main table from being visible.
• Example database in examples/books/book.data extended to include books with unknown authors.

Feedback to <mike@sql.z3950.org> is welcome!