Merge branch 'develop' into feature/language

CMakeLists.txt

packages/CLI11/.ci/make_and_test.sh

packages/CLI11/.gitmodules

packages/CLI11/.gitrepo

packages/CLI11/.travis.yml

packages/CLI11/CHANGELOG.md

packages/CLI11/CMakeLists.txt

packages/CLI11/LICENSE

packages/CLI11/README.md

packages/CLI11/docs/CLI11.svg

packages/CLI11/docs/CLI11_100.png

packages/CLI11/docs/CLI11_300.png

packages/CLI11/docs/Doxyfile

packages/CLI11/examples/CMakeLists.txt

packages/CLI11/examples/enum.cpp

packages/CLI11/examples/json.cpp

packages/CLI11/examples/nested.cpp

packages/CLI11/examples/subcom_in_files/subcommand_a.cpp

packages/CLI11/examples/validators.cpp

packages/CLI11/extern/json