Обсуждение: pgsql: doc: Clean up some recently added PL/pgSQL documentation

doc: Clean up some recently added PL/pgSQL documentation

- Capitalize titles consistently.
- Fix some grammar.
- Group "Obtaining Information About an Error" under "Trapping Errors",
  but make "Obtaining the Call Stack Context Information" its own
  section, since it's not about errors.

Branch
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master

Details
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http://git.postgresql.org/pg/commitdiff/232f1475dce23e2fdd0568b35e9a7c470ae6c8ae

Modified Files
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doc/src/sgml/plpgsql.sgml |   39 ++++++++++++++-------------------------
1 file changed, 14 insertions(+), 25 deletions(-)