[pgpool-committers: 5505] pgpool: Doc: add "performance" chapter to doc.

[Tatsuo Ishii]

Doc: add "performance" chapter to doc.

This is just a starting up and more contents will be coming.
After completing the English doc, Japanese doc will come.

Branch
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master

Details
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https://git.postgresql.org/gitweb?p=pgpool2.git;a=commitdiff;h=c706e0d6eaa7c0c39fa7ca2e86fba3f1fbcd1390

Modified Files
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doc/src/sgml/filelist.sgml    |  1 +
doc/src/sgml/performance.sgml | 79 +++++++++++++++++++++++++++++++++++++++++++
2 files changed, 80 insertions(+)