Part 2: Make enum -> enum class

[TobiKattmann]

Hi all,

this is the continuation of #1242 . Change of the enum's in option_structure.hpp into enum class. This has the benefit of no implicit conversion to int and therefore increased safety with the enum type -> c++ core guidelines.

If you want to sponsor a commit (which I highly recommend ;) ) then a good approach is to

1. make your enum of choice an enum class and remove the associated numbers.
2. Rename here if reasonable, i,.e. ENUM_INLET_TYPE can be just INLET_TYPE. Also the option names to not be redundant so e.g. INLET_TYPE::PRESSURE_INLET_TYPE could become INLET_TYPE::PRESSURE
3. Add a NONE or NO_THING option if needed. Often the global NONE option is and that made a lot of people very angry and has been widely regarded as a bad move 🧙
4. then you go to CConfig.c/hpp and change the option type and everything there (because in the CConfig class the variable is usually defined). Find the GetKind_yourOption and search the code base for that Get function.
5. Once all search results and the following function bodies are changed just compile and fix until the code builds
6. Special care for switch statements: If not all options are present make a default; break; line -> otherwise the automated builds will fail on a warning (clang is used, I found gcc does only complain with an additional flag)
7. commit at best just 1 commit with a clear message and push. That makes reverting easier if it fails and introduced some non-obvious error

Have fun :)

Related Work

#1242

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• I am submitting my contribution to the develop branch.
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• I have added a test case that demonstrates my contribution, if necessary.
• I have updated appropriate documentation (Tutorials, Docs Page, config_template.cpp) , if necessary.

[TobiKattmann]

Added a NO_RECORDING option as the global NONE was used

[TobiKattmann]

not used any more, nice 👍

[TobiKattmann]

Codefactor is just complainig about the usual CIncEulerSolver. All other test pass, so I'll merge this and continue in Part III.
Coming to a repository near you soon. 🎦