pgsql: In relevant log messages, indicate whether vacuums are aggressiv

In relevant log messages, indicate whether vacuums are aggressive.

Kyotaro Horiguchi, reviewed Masahiko Sawada, David G. Johnston, Álvaro
Herrera, and me. Grammar correction to the final posted patch by me.

Discussion: http://postgr.es/m/[email protected]

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/b55509332f50f998b6e8b3830a51c5b9d8f666aa

Modified Files
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src/backend/commands/vacuumlazy.c | 21 ++++++++++++++++-----
1 file changed, 16 insertions(+), 5 deletions(-)