Finite Field support #473

Job	Run time
ubuntu-latest\|debug\|--enable-mcsat\|CC=gcc CXX=g++	8m 27s
ubuntu-latest\|debug\|--enable-mcsat\|CC=clang CXX=clang++	8m 54s
ubuntu-latest\|debug\|--enable-thread-safety\|CC=gcc CXX=g++	4m 5s
ubuntu-latest\|debug\|--enable-thread-safety\|CC=clang CXX=clang++	4m 26s
ubuntu-latest\|release\|--enable-mcsat\|CC=gcc CXX=g++	5m 18s
ubuntu-latest\|release\|--enable-mcsat\|CC=clang CXX=clang++	5m 31s
ubuntu-latest\|release\|--enable-thread-safety\|CC=gcc CXX=g++	2m 26s
ubuntu-latest\|release\|--enable-thread-safety\|CC=clang CXX=clang++	2m 46s
ubuntu-latest\|gcov\|--enable-mcsat\|CC=gcc CXX=g++	8m 20s
ubuntu-latest\|debug\|--enable-thread-safety --enable-mcsat\|CC=gcc CXX=g++	8m 3s
	58m 16s

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