Squashed 'extensions/DFDiagram/' content from commit bb52298

git-subtree-dir: extensions/DFDiagram
git-subtree-split: bb5229893ae4ee5de61b356d7bf8fd5743b5efb0
Merge commit '2cc6cbef53857d7bada23d2c9b5cee3a9590853e' as 'extensions/DFDiagram'
DFDiagram