Add extracted tools: CitrineOS, OpenOCPP, ShapeShifter

- CitrineOS core extracted (CSMS OCPP 2.0.1)
- OpenOCPP extracted (firmware OCPP 1.6J/2.0.1)
- ShapeShifter library installed (pip install -e)
- ShapeShifter specification extracted
- EVerest extracted

TODO updated with progress

tools/EVerest-main/modules/HardwareDrivers/PowerMeters/IsabellenhuetteIemDcr/tests/README.md

@@ -0,0 +1,10 @@
+## Unit tests with GTest
+A series of unit tests checks the implemented business logic of the controller. 
+The unit tests require GoogleTest (GTest). This can be installed via
+```bash
+apt install libgtest-dev
+```
+Please do not forget to compile GTest library.
+
+To run the tests, please issue compiler switch -DBUILD_TESTING=ON which will
+enable EVEREST_CORE_BUILD_TESTING on which these unit tests relate.