Migration to new architecture.

[arapelle]

• Use cmtk-0.10.0.
• Move cmake/cmtk to external/cmake/cmtk.
• Move header from include/ to include/arba/.
• Add inline namespace arba in hcpp files.
• Add unit test project_version_tests.cpp.
• Modify a unit test to check if arba namespace is present.
• Move CMake script and config to cmake/scripts|config.
• Make sure project version header is included in basic_cmake_project.
• Use prefix arba-.