Stop in cmake configure when the compiler is not supported

Summary

Closes #1964 (closed).

Throw an error in CMake instead of a warning when the compiler is not supported.

The fact that clang is not available by default on CentOS 7 and must be installed with devtoolset

Copyright

The copyright owner is CNES and has signed the ORFEO ToolBox Contributor License Agreement.

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• Optionally, run git diff develop... -U0 --no-color | clang-format-diff.py -p1 -i on latest changes and commit