Finite Field support #475

Job	Run time
ubuntu-latest\|debug\|--enable-mcsat\|CC=gcc CXX=g++	5m 51s
ubuntu-latest\|debug\|--enable-mcsat\|CC=clang CXX=clang++	5m 53s
ubuntu-latest\|debug\|--enable-thread-safety\|CC=gcc CXX=g++	3m 58s
ubuntu-latest\|debug\|--enable-thread-safety\|CC=clang CXX=clang++	4m 14s
ubuntu-latest\|release\|--enable-mcsat\|CC=gcc CXX=g++	5m 48s
ubuntu-latest\|release\|--enable-mcsat\|CC=clang CXX=clang++	5m 34s
ubuntu-latest\|release\|--enable-thread-safety\|CC=gcc CXX=g++	2m 21s
ubuntu-latest\|release\|--enable-thread-safety\|CC=clang CXX=clang++	3m 12s
ubuntu-latest\|gcov\|--enable-mcsat\|CC=gcc CXX=g++	5m 52s
ubuntu-latest\|debug\|--enable-thread-safety --enable-mcsat\|CC=gcc CXX=g++	5m 51s
	48m 34s

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