revert: add transaction processing chapter with internals info

Bruce Momjian <bruce@momjian.us>

Commit: f79cca5bfd2250c56e93f32a21bd3cd39be07724
Author: Bruce Momjian <bruce@momjian.us>
Date: 2022-12-01T15:45:08Z
Releases: 15.2
revert:  add transaction processing chapter with internals info

This doc patch (master hash 66bc9d2d3e) was decided to be too
significant for backpatching, so reverted in all but master.  Also fix
SGML file header comment in master.

Reported-by:  	Peter Eisentraut

Discussion: https://postgr.es/m/c6304b19-6ff7-f3af-0148-cf7aa7e2fbfd@enterprisedb.com

Backpatch-through: 11

Files

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