Escape the backslash to avoid warning in PostgreSQL 9.0-

Escape the backslash to avoid warning in PostgreSQL 9.0-

In PostgreSQL 9.1, "standard_conforming_strings" is ON by default and
there's no warning - but previous versions of PostgreSQL will see the
backslash and throw a warning about how you haven't escaped the
backslash. Thanks to Thomas Berezansky for noticing.

Signed-off-by: Dan Scott <dan@coffeecode.net>