[pgpool-committers: 4377] pgpool: Enhance documents.

[Tatsuo Ishii]

Enhance documents.

restrictions.sgml: use "xreflabel" in the sect1 title so that xref can
render proper label.

runtime.sgml: enhance "Running mode of Pgpool-II" section.

Branch
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V3_7_STABLE

Details
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https://git.postgresql.org/gitweb?p=pgpool2.git;a=commitdiff;h=87ebfb7366eb03680f95b5bf8d9829c29a623182

Modified Files
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doc/src/sgml/restrictions.sgml |  2 +-
doc/src/sgml/runtime.sgml      | 80 +++++++++++++++++++++++++++++-------------
2 files changed, 57 insertions(+), 25 deletions(-)