pgsql: Provide a parenthesized-options syntax for VACUUM, analogous to

Log Message:
-----------
Provide a parenthesized-options syntax for VACUUM, analogous to that recently
adopted for EXPLAIN.  This will allow additional options to be implemented
in future without having to make them fully-reserved keywords.  The old syntax
remains available for existing options, however.

Itagaki Takahiro

Modified Files:
--------------
    pgsql/doc/src/sgml:
        maintenance.sgml (r1.96 -> r1.97)
        (http://anoncvs.postgresql.org/cvsweb.cgi/pgsql/doc/src/sgml/maintenance.sgml?r1=1.96&r2=1.97)
    pgsql/doc/src/sgml/ref:
        vacuum.sgml (r1.55 -> r1.56)
        (http://anoncvs.postgresql.org/cvsweb.cgi/pgsql/doc/src/sgml/ref/vacuum.sgml?r1=1.55&r2=1.56)
    pgsql/src/backend/commands:
        analyze.c (r1.141 -> r1.142)
        (http://anoncvs.postgresql.org/cvsweb.cgi/pgsql/src/backend/commands/analyze.c?r1=1.141&r2=1.142)
        vacuum.c (r1.395 -> r1.396)
        (http://anoncvs.postgresql.org/cvsweb.cgi/pgsql/src/backend/commands/vacuum.c?r1=1.395&r2=1.396)
        vacuumlazy.c (r1.123 -> r1.124)
        (http://anoncvs.postgresql.org/cvsweb.cgi/pgsql/src/backend/commands/vacuumlazy.c?r1=1.123&r2=1.124)
    pgsql/src/backend/nodes:
        copyfuncs.c (r1.450 -> r1.451)
        (http://anoncvs.postgresql.org/cvsweb.cgi/pgsql/src/backend/nodes/copyfuncs.c?r1=1.450&r2=1.451)
        equalfuncs.c (r1.372 -> r1.373)
        (http://anoncvs.postgresql.org/cvsweb.cgi/pgsql/src/backend/nodes/equalfuncs.c?r1=1.372&r2=1.373)
    pgsql/src/backend/parser:
        gram.y (r2.692 -> r2.693)
        (http://anoncvs.postgresql.org/cvsweb.cgi/pgsql/src/backend/parser/gram.y?r1=2.692&r2=2.693)
    pgsql/src/backend/postmaster:
        autovacuum.c (r1.104 -> r1.105)
        (http://anoncvs.postgresql.org/cvsweb.cgi/pgsql/src/backend/postmaster/autovacuum.c?r1=1.104&r2=1.105)
    pgsql/src/backend/tcop:
        utility.c (r1.316 -> r1.317)
        (http://anoncvs.postgresql.org/cvsweb.cgi/pgsql/src/backend/tcop/utility.c?r1=1.316&r2=1.317)
    pgsql/src/include/nodes:
        parsenodes.h (r1.414 -> r1.415)
        (http://anoncvs.postgresql.org/cvsweb.cgi/pgsql/src/include/nodes/parsenodes.h?r1=1.414&r2=1.415)
    pgsql/src/test/regress/expected:
        vacuum.out (r1.1 -> r1.2)
        (http://anoncvs.postgresql.org/cvsweb.cgi/pgsql/src/test/regress/expected/vacuum.out?r1=1.1&r2=1.2)
    pgsql/src/test/regress/sql:
        vacuum.sql (r1.1 -> r1.2)
        (http://anoncvs.postgresql.org/cvsweb.cgi/pgsql/src/test/regress/sql/vacuum.sql?r1=1.1&r2=1.2)