[sys][sql] Replaced "1"/"0" query comparison values with "TRUE"/"FALSE"

This allows generated SQL to be compatible with Postgres
while still keeping compatibility with MySQL

PostgreHX link: https://github.com/jdonaldson/postgrehx
SQL Fiddle links showing that "1" does not work in PostgreSQL
and "TRUE" works for both PostgreSQL and MySQL:
MYSQL 5.5.32 http://sqlfiddle.com/#!2/78ef27/4
PostgreSQL 9.3.1 http://sqlfiddle.com/#!15/efc23/2