Squashed 'R-Extended/' changes from 4c5a2f5..c0f9ad7

c0f9ad7 update R-Extended README.md

git-subtree-dir: R-Extended
git-subtree-split: c0f9ad7b8d2fdbe06f7b3412a3bdd5ba09f4669e
Merge commit 'c450607fadf763f05f0eebf3e1ed5a716f484310'