mdb-export: Add boolean words option (TRUE/FALSE)

Adds "-B" (--boolean-words) option to mdb-export, which will reconfigure
mdb/data.c to export TRUE/FALSE for boolean values instead of 1/0.  The
option is needed to support BOOLEAN fields on PostgreSQL, which will not
implicitly cast bare 1/0 into a BOOLEAN value.  Value literals are the
SQL TRUE/FALSE, and _quoted_ words meaning true/false and _quoted_
'1'/'0'.  With this flag the SQL TRUE/FALSE values are output, which should
work with several SQL databases.

PostgreSQL Reference:

http://www.postgresql.org/docs/current/static/datatype-boolean.html

(note for KEXI: note used but added to make data.c merges more cleanly)

FIXED-IN:3.1.1
mdbtools 8b1db6c08edbdf