pgsql: Normalize fgets() calls to use sizeof() for calculating the

Log Message:
-----------
Normalize fgets() calls to use sizeof() for calculating the buffer size
where possible, and fix some sites that apparently thought that fgets()
will overwrite the buffer by one byte.

Also add some strlcpy() to eliminate some weird memory handling.

Modified Files:
--------------
    pgsql/contrib/tsearch2:
        dict_syn.c (r1.11 -> r1.12)
        (http://developer.postgresql.org/cvsweb.cgi/pgsql/contrib/tsearch2/dict_syn.c.diff?r1=1.11&r2=1.12)
        stopword.c (r1.10 -> r1.11)
        (http://developer.postgresql.org/cvsweb.cgi/pgsql/contrib/tsearch2/stopword.c.diff?r1=1.10&r2=1.11)
    pgsql/src/backend/access/transam:
        xlog.c (r1.262 -> r1.263)
        (http://developer.postgresql.org/cvsweb.cgi/pgsql/src/backend/access/transam/xlog.c.diff?r1=1.262&r2=1.263)
    pgsql/src/bin/pg_dump:
        pg_backup_files.c (r1.29 -> r1.30)
        (http://developer.postgresql.org/cvsweb.cgi/pgsql/src/bin/pg_dump/pg_backup_files.c.diff?r1=1.29&r2=1.30)
    pgsql/src/bin/psql:
        common.c (r1.132 -> r1.133)
        (http://developer.postgresql.org/cvsweb.cgi/pgsql/src/bin/psql/common.c.diff?r1=1.132&r2=1.133)
        copy.c (r1.73 -> r1.74)
        (http://developer.postgresql.org/cvsweb.cgi/pgsql/src/bin/psql/copy.c.diff?r1=1.73&r2=1.74)
        prompt.c (r1.49 -> r1.50)
        (http://developer.postgresql.org/cvsweb.cgi/pgsql/src/bin/psql/prompt.c.diff?r1=1.49&r2=1.50)
    pgsql/src/interfaces/libpq:
        fe-connect.c (r1.341 -> r1.342)
        (http://developer.postgresql.org/cvsweb.cgi/pgsql/src/interfaces/libpq/fe-connect.c.diff?r1=1.341&r2=1.342)
        fe-secure.c (r1.91 -> r1.92)
        (http://developer.postgresql.org/cvsweb.cgi/pgsql/src/interfaces/libpq/fe-secure.c.diff?r1=1.91&r2=1.92)
    pgsql/src/tools/entab:
        entab.c (r1.17 -> r1.18)
        (http://developer.postgresql.org/cvsweb.cgi/pgsql/src/tools/entab/entab.c.diff?r1=1.17&r2=1.18)