pgsql: Merge the list of statistics functions into the view documentati

Merge the list of statistics functions into the view documentation

Most people won't read them individually anyway, it's an easy way to find
them, and it's a lot of duplicated information if they are kept in two
different places.

Branch
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master

Details
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http://git.postgresql.org/pg/commitdiff/ddfc2d9a3705d246c7f262d1f3745d2cf64da1bd

Modified Files
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doc/src/sgml/monitoring.sgml |  940 ++++++++++--------------------------------
1 files changed, 217 insertions(+), 723 deletions(-)