Add GMP extraction and tests to the bench

bench/bench

examples/in_progress/multiprecision/Makefile

examples/in_progress/multiprecision/build/.gitignore

examples/in_progress/multiprecision/include/config.h

examples/in_progress/multiprecision/include/fac_table.h

examples/in_progress/multiprecision/include/fib_table.h

examples/in_progress/multiprecision/include/gmp-impl.h

examples/in_progress/multiprecision/include/gmp-mparam.h

examples/in_progress/multiprecision/include/gmp.h

examples/in_progress/multiprecision/include/gmpxx.h

examples/in_progress/multiprecision/include/longlong.h

examples/in_progress/multiprecision/include/mp_bases.h

examples/in_progress/multiprecision/include/trialdivtab.h