Thread: pgsql: Tweak the code in a couple of places to try to deliver more

Log Message:
-----------
Tweak the code in a couple of places to try to deliver more user-friendly
error messages when a single COPY line is too long for us to handle.  Per
example from Johann Spies.

Modified Files:
--------------
    pgsql/src/backend/lib:
        stringinfo.c (r1.45 -> r1.46)
        (http://developer.postgresql.org/cvsweb.cgi/pgsql/src/backend/lib/stringinfo.c.diff?r1=1.45&r2=1.46)
    pgsql/src/backend/utils/mb:
        mbutils.c (r1.62 -> r1.63)
        (http://developer.postgresql.org/cvsweb.cgi/pgsql/src/backend/utils/mb/mbutils.c.diff?r1=1.62&r2=1.63)