pgsql: doc: Use more concise wording for pl/pgSQL TG_ variables

doc: Use more concise wording for pl/pgSQL TG_ variables

To improve readability of the TG_ variables definition lists, this moves
the datatypes up to the defined term to avoid having each entry start
with "Data type". This also removes redundant wording that that didn't
carry any information from the descriptions.

Author: Christoph Berg <myon@debian.org>
Reviewed-by: Dagfinn Ilmari Mannsåker <ilmari@ilmari.org>
Discussion: https://postgr.es/m/Yw4Noe3A2s87A0qq@msg.df7cb.de

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/b7f3981756d314d32cca27b5c3d31bdd58b6ff06

Modified Files
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doc/src/sgml/plpgsql.sgml | 67 ++++++++++++++++++++---------------------------
1 file changed, 28 insertions(+), 39 deletions(-)