Refactoring: Running the Direct Program

        $> perl get_3_intersection.pl --tests-only
        ok 1 - Running tests only
        List::Compare::Functional version: 0.38000
        ok 2 - Got expected intersection
        1..2

        $> perl get_3_intersection.pl --benchmarks-only
        ok 1 - Running benchmarks only
        List::Compare::Functional version: 0.38000
        timethis 1000:  1 wallclock secs ( 1.32 usr +  0.00 sys =  1.32 CPU) @ 757.58/s (n=1000)
        1..1

        $> perl get_3_intersection.pl
        List::Compare::Functional version: 0.38000
        ok 1 - Got expected intersection
        timethis 1000:  1 wallclock secs ( 1.35 usr +  0.00 sys =  1.35 CPU) @ 740.74/s (n=1000)
        1..1