pgsql: Use 0x01 for newlines in saved history.

Log Message:
-----------
Use 0x01 for newlines in saved history.  It was determined to be not
used by multi-byte sequences, but futher invesetigation might prove this
to be false.

Modified Files:
--------------
    pgsql/src/bin/psql:
        input.c (r1.47 -> r1.48)
        (http://developer.postgresql.org/cvsweb.cgi/pgsql/src/bin/psql/input.c.diff?r1=1.47&r2=1.48)