set libpng external in the 21.9

See merge request atlas/athena!37740

Fixed IDPVM output file name in ttbar ART test

See merge request atlas/athena!37728

Improve VMM CPU performance

See merge request atlas/athena!37699

Sweeping !37478 from 21.3 to 21.9.
update unit test reference due to update of IdDictParser xml

See merge request atlas/athena!37719

John Derek Chapman authored 4 years ago and Atlas Nightlybuild committed 4 years ago

update unit test reference due to update of IdDictParser xml

See merge request atlas/athena!37478

(cherry picked from commit 1d7b23e2)

14e7fc3a update unit test reference due to update of IdDictParser xml

hasChargeAboveThreshold only start close to a first possible peak; introduce a quick check on the total charge without vmm to stop early

Re-instate VMM shaper

See merge request atlas/athena!37686

Initial implementation of HGTD specific readout geometry classes

See merge request atlas/athena!37592

ATLAS-P2-ITK-17-06-00 backward compatibility changes

See merge request atlas/athena!37656

This reverts merge request !37433

Set default filenames for pixel XML

See merge request atlas/athena!37664