Use unique_ptr in Bookkeeper for front ends

Make ownership of the FrontEnd objects explicit in the Bookkeeper using unique_ptr. Should fix the memory leak reported in #214 (closed).

added 1 commit

• 681034bc - Fix clang's side effect error on typeid

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added 1 deleted label

Looks good to me

added 54 commits

• 681034bc...7301366f - 51 commits from branch devel
• 20701d35 - Use unique_ptr in Bookkeeper for front ends
• 33a24bcf - Fix clang's side effect error on typeid
• 1d81cce7 - Remove unnecessary std::move

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resolved all threads

enabled an automatic merge when the pipeline for dc2e3213 succeeds

mentioned in commit 763e5935

merged