Thread: pgsql: Doc: update src/tools/pginclude/README.

Doc: update src/tools/pginclude/README.

Commit f62975b2a made headerscheck and cpluspluscheck a little
smarter than this documentation gave them credit for.  Make
their docs match current reality.  Also add a warning about the
layer of dust that has settled on the rest of these scripts.

Discussion: https://postgr.es/m/769950.1684797558@sss.pgh.pa.us

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/be3f62ae6e9839b10db0052a973e5fdc5b789abc

Modified Files
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src/tools/pginclude/README | 23 +++++++++++++++--------
1 file changed, 15 insertions(+), 8 deletions(-)