pgsql: Add "source file" and "source line" information to each GUC

Log Message:
-----------
Add "source file" and "source line" information to each GUC variable.

initdb forced due to changes in the pg_settings view.

Magnus Hagander and Alvaro Herrera.

Modified Files:
--------------
    pgsql/doc/src/sgml:
        catalogs.sgml (r2.172 -> r2.173)
        (http://anoncvs.postgresql.org/cvsweb.cgi/pgsql/doc/src/sgml/catalogs.sgml?r1=2.172&r2=2.173)
    pgsql/src/backend/utils/misc:
        guc-file.l (r1.56 -> r1.57)
        (http://anoncvs.postgresql.org/cvsweb.cgi/pgsql/src/backend/utils/misc/guc-file.l?r1=1.56&r2=1.57)
        guc.c (r1.470 -> r1.471)
        (http://anoncvs.postgresql.org/cvsweb.cgi/pgsql/src/backend/utils/misc/guc.c?r1=1.470&r2=1.471)
    pgsql/src/include/catalog:
        catversion.h (r1.484 -> r1.485)
        (http://anoncvs.postgresql.org/cvsweb.cgi/pgsql/src/include/catalog/catversion.h?r1=1.484&r2=1.485)
        pg_proc.h (r1.513 -> r1.514)
        (http://anoncvs.postgresql.org/cvsweb.cgi/pgsql/src/include/catalog/pg_proc.h?r1=1.513&r2=1.514)
    pgsql/src/include/utils:
        guc_tables.h (r1.41 -> r1.42)
        (http://anoncvs.postgresql.org/cvsweb.cgi/pgsql/src/include/utils/guc_tables.h?r1=1.41&r2=1.42)
    pgsql/src/test/regress/expected:
        rules.out (r1.141 -> r1.142)
        (http://anoncvs.postgresql.org/cvsweb.cgi/pgsql/src/test/regress/expected/rules.out?r1=1.141&r2=1.142)