Whole-tree reformat

[pmatos]

This follows discussions from #3413.
Followup commits add clang-format file, script and blame ignore lists.

[pmatos]

How was this change generated?

Grab #3572 and the git repo at sha a9b7ad8.
Run at the root of the repo:

find . -iname '*.h' -o -iname '*.cpp' -exec python3 Scripts/clang-format.py -i \{\} \;

The resulting repo should match the changes in this commit.

[pmatos]

Pushed a new reformat. This time using reformatting using clang-format-16 through:

for file in `git ls-files '*.cpp' '*.h'`; do python3 Scripts/clang-format.py -i ${file}; done

The diff stat is: 447 files changed, 77599 insertions(+), 72080 deletions(-)

[pmatos]

The stat looks correct. The different between the current stat and the one I mentioned earlier in #3571 (comment) is due to the PR #3574.