doc: modernise example(s)

example/pyproject.toml

example/src/AverageCurrent.cc

example/src/Controller.cc

example/src/ExampleApp.cc

example/src/SetpointRamp.cc

example/src_factory/FactoryInstance.cc

example2/CMakeLists.txt

example2/COPYING

example2/COPYING.LESSER

example2/This_project_uses_the_project-template.txt

example2/cmake

example2/config/demoApp2-DoocsVariableConfig.xml

example2/config/demo_example2.conf

example2/config/example2.dmap

example2/config/oven.map

example2/demoApp2.cc

example2/oven_sim/oven_sim.py

example2a/CMakeLists.txt

example2a/COPYING

example2a/COPYING.LESSER