pgsql: Autovacuum loose end mop-up.

Log Message:
-----------
Autovacuum loose end mop-up.  Provide autovacuum-specific vacuum cost
delay and limit, both as global GUCs and as table-specific entries in
pg_autovacuum.  stats_reset_on_server_start is now OFF by default,
but a reset is forced if we did WAL replay.  XID-wrap vacuums do not
ANALYZE, but do FREEZE if it's a template database.  Alvaro Herrera

Modified Files:
--------------
    pgsql/doc/src/sgml:
        catalogs.sgml (r2.110 -> r2.111)
        (http://developer.postgresql.org/cvsweb.cgi/pgsql/doc/src/sgml/catalogs.sgml.diff?r1=2.110&r2=2.111)
        runtime.sgml (r1.343 -> r1.344)
        (http://developer.postgresql.org/cvsweb.cgi/pgsql/doc/src/sgml/runtime.sgml.diff?r1=1.343&r2=1.344)
    pgsql/src/backend/access/transam:
        xlog.c (r1.214 -> r1.215)
        (http://developer.postgresql.org/cvsweb.cgi/pgsql/src/backend/access/transam/xlog.c.diff?r1=1.214&r2=1.215)
    pgsql/src/backend/libpq:
        hba.c (r1.146 -> r1.147)
        (http://developer.postgresql.org/cvsweb.cgi/pgsql/src/backend/libpq/hba.c.diff?r1=1.146&r2=1.147)
    pgsql/src/backend/postmaster:
        autovacuum.c (r1.2 -> r1.3)
        (http://developer.postgresql.org/cvsweb.cgi/pgsql/src/backend/postmaster/autovacuum.c.diff?r1=1.2&r2=1.3)
        pgstat.c (r1.104 -> r1.105)
        (http://developer.postgresql.org/cvsweb.cgi/pgsql/src/backend/postmaster/pgstat.c.diff?r1=1.104&r2=1.105)
        postmaster.c (r1.461 -> r1.462)
        (http://developer.postgresql.org/cvsweb.cgi/pgsql/src/backend/postmaster/postmaster.c.diff?r1=1.461&r2=1.462)
    pgsql/src/backend/tcop:
        postgres.c (r1.456 -> r1.457)
        (http://developer.postgresql.org/cvsweb.cgi/pgsql/src/backend/tcop/postgres.c.diff?r1=1.456&r2=1.457)
    pgsql/src/backend/utils/init:
        flatfiles.c (r1.13 -> r1.14)
        (http://developer.postgresql.org/cvsweb.cgi/pgsql/src/backend/utils/init/flatfiles.c.diff?r1=1.13&r2=1.14)
        postinit.c (r1.156 -> r1.157)
        (http://developer.postgresql.org/cvsweb.cgi/pgsql/src/backend/utils/init/postinit.c.diff?r1=1.156&r2=1.157)
    pgsql/src/backend/utils/misc:
        guc.c (r1.280 -> r1.281)
        (http://developer.postgresql.org/cvsweb.cgi/pgsql/src/backend/utils/misc/guc.c.diff?r1=1.280&r2=1.281)
        postgresql.conf.sample (r1.156 -> r1.157)

(http://developer.postgresql.org/cvsweb.cgi/pgsql/src/backend/utils/misc/postgresql.conf.sample.diff?r1=1.156&r2=1.157)
    pgsql/src/include/catalog:
        catversion.h (r1.295 -> r1.296)
        (http://developer.postgresql.org/cvsweb.cgi/pgsql/src/include/catalog/catversion.h.diff?r1=1.295&r2=1.296)
        pg_autovacuum.h (r1.1 -> r1.2)
        (http://developer.postgresql.org/cvsweb.cgi/pgsql/src/include/catalog/pg_autovacuum.h.diff?r1=1.1&r2=1.2)
    pgsql/src/include/libpq:
        hba.h (r1.39 -> r1.40)
        (http://developer.postgresql.org/cvsweb.cgi/pgsql/src/include/libpq/hba.h.diff?r1=1.39&r2=1.40)
    pgsql/src/include:
        pgstat.h (r1.34 -> r1.35)
        (http://developer.postgresql.org/cvsweb.cgi/pgsql/src/include/pgstat.h.diff?r1=1.34&r2=1.35)
    pgsql/src/include/postmaster:
        autovacuum.h (r1.1 -> r1.2)
        (http://developer.postgresql.org/cvsweb.cgi/pgsql/src/include/postmaster/autovacuum.h.diff?r1=1.1&r2=1.2)
    pgsql/src/include/tcop:
        tcopprot.h (r1.76 -> r1.77)
        (http://developer.postgresql.org/cvsweb.cgi/pgsql/src/include/tcop/tcopprot.h.diff?r1=1.76&r2=1.77)