pgsql: Update example of process titles shown by "ps".

Update example of process titles shown by "ps".

This example was quite old: it lacked the WAL writer and autovac launcher
as well as the more recently added checkpointer. Linux "ps" seems to show
slightly different stuff now too.

Branch
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master

Details
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http://git.postgresql.org/pg/commitdiff/f35ebd2aa1a2c5d99e859abed488b67c4e3694ff

Modified Files
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doc/src/sgml/monitoring.sgml | 30 +++++++++++++++++++-----------
1 files changed, 19 insertions(+), 11 deletions(-)