Finite Field support #471

Job	Run time
ubuntu-latest\|debug\|--enable-mcsat\|CC=gcc CXX=g++	8m 7s
ubuntu-latest\|debug\|--enable-mcsat\|CC=clang CXX=clang++	9m 38s
ubuntu-latest\|debug\|--enable-thread-safety\|CC=gcc CXX=g++	3m 56s
ubuntu-latest\|debug\|--enable-thread-safety\|CC=clang CXX=clang++	4m 27s
ubuntu-latest\|release\|--enable-mcsat\|CC=gcc CXX=g++	5m 34s
ubuntu-latest\|release\|--enable-mcsat\|CC=clang CXX=clang++	5m 33s
ubuntu-latest\|release\|--enable-thread-safety\|CC=gcc CXX=g++	2m 22s
ubuntu-latest\|release\|--enable-thread-safety\|CC=clang CXX=clang++	3m 0s
ubuntu-latest\|gcov\|--enable-mcsat\|CC=gcc CXX=g++	8m 33s
ubuntu-latest\|debug\|--enable-thread-safety --enable-mcsat\|CC=gcc CXX=g++	8m 32s
	59m 42s

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