Clarify VACUUM FULL exclusion in total_vacuum_time docs

Hi,

Since last_vacuum and vacuum_count in pg_stat_all_tables explicitly mention
that they don't include VACUUM FULL ("not counting VACUUM FULL"), I think
we should add the same clarification to the description of total_vacuum_time.
This field also excludes VACUUM FULL, and without this note, users might
mistakenly think the time spent on VACUUM FULL is included. Thought?

<structfield>total_vacuum_time</structfield> <type>double precision</type>
</para>
<para>
- Total time this table has been manually vacuumed, in milliseconds.
+ Total time this table has been manually vacuumed, in milliseconds
+ (not counting <command>VACUUM FULL</command>).
(This includes the time spent sleeping due to cost-based delays.)
</para></entry>
</row>

Regards,

--
Fujii Masao
NTT DATA Japan Corporation