pgsql: Code and docs review for ALTER TABLE INHERIT/NO INHERIT patch.

Log Message:
-----------
Code and docs review for ALTER TABLE INHERIT/NO INHERIT patch.

Modified Files:
--------------
    pgsql/doc/src/sgml:
        ddl.sgml (r1.63 -> r1.64)
        (http://developer.postgresql.org/cvsweb.cgi/pgsql/doc/src/sgml/ddl.sgml.diff?r1=1.63&r2=1.64)
    pgsql/doc/src/sgml/ref:
        alter_table.sgml (r1.90 -> r1.91)
        (http://developer.postgresql.org/cvsweb.cgi/pgsql/doc/src/sgml/ref/alter_table.sgml.diff?r1=1.90&r2=1.91)
    pgsql/src/backend/commands:
        tablecmds.c (r1.205 -> r1.206)
        (http://developer.postgresql.org/cvsweb.cgi/pgsql/src/backend/commands/tablecmds.c.diff?r1=1.205&r2=1.206)
    pgsql/src/backend/nodes:
        copyfuncs.c (r1.351 -> r1.352)
        (http://developer.postgresql.org/cvsweb.cgi/pgsql/src/backend/nodes/copyfuncs.c.diff?r1=1.351&r2=1.352)
        equalfuncs.c (r1.285 -> r1.286)
        (http://developer.postgresql.org/cvsweb.cgi/pgsql/src/backend/nodes/equalfuncs.c.diff?r1=1.285&r2=1.286)
    pgsql/src/backend/parser:
        gram.y (r2.566 -> r2.567)
        (http://developer.postgresql.org/cvsweb.cgi/pgsql/src/backend/parser/gram.y.diff?r1=2.566&r2=2.567)
    pgsql/src/include/nodes:
        parsenodes.h (r1.332 -> r1.333)
        (http://developer.postgresql.org/cvsweb.cgi/pgsql/src/include/nodes/parsenodes.h.diff?r1=1.332&r2=1.333)
    pgsql/src/test/regress/expected:
        alter_table.out (r1.98 -> r1.99)

(http://developer.postgresql.org/cvsweb.cgi/pgsql/src/test/regress/expected/alter_table.out.diff?r1=1.98&r2=1.99)