Remove code that is no longer required

Remove

• CMake check for unused feature
• Work arounds for no-longer supported compilers

approved this merge request

changed the description

approved this merge request

added 9 commits

• 08647369...30fe4dc3 - 5 commits from branch master
• d9e56b7a - [cmake] Drop check for std::experimental::make_array
• dfee6d47 - Remove code to work around GCC 5.4 crash
• 08ba6ff1 - Revert "Work around a nasty compiler bug in GCC 6.3"
• 841cbfd8 - Revert "FieldVector: do not use defaulted copy constructor with GCC 5.4"

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enabled an automatic merge when the pipeline for 841cbfd8 succeeds

merged

mentioned in commit 266f9659