add definition of constraints #2905

Job	Run time
ubuntu-clang-deprecated Debug	21m 44s
ubuntu-clang-deprecated Release	22m 51s
ubuntu-clang-quaternions Debug	22m 44s
ubuntu-clang-quaternions Release	22m 48s
ubuntu-clang-tbb Debug	23m 2s
ubuntu-clang-tbb Release	24m 58s
ubuntu-clang-cayleymap Debug	22m 11s
ubuntu-clang-cayleymap Release	22m 57s
ubuntu-clang-system-libs Debug	21m 39s
ubuntu-clang-system-libs Release	22m 42s
ubuntu-no-boost Debug	21m 31s
ubuntu-no-boost Release	22m 36s
ubuntu-no-unstable Debug	18m 41s
ubuntu-no-unstable Release	18m 58s
	5h 9m 22s

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