Merge pull request #440 from hflynn/images_tidy

Images tidy dev_4_4
Merge pull request #442 from sbesson/11361_homebrew_python

Homebrew and Python
Merge pull request #443 from hflynn/policy_images

Policy images
HowToCreateAService.txt: remove broken links.
Properties.txt: remove broken links.
SecuritySystem.txt: remove broken links.
merge dev_4_4 -D org -I include -E exclude: PR 368 (Cpp: Correct content and markup)
merge dev_4_4 -D org -I include -E exclude: PR 446 (Fix doc links to removed client component (see #11390))