Add sumloop benchmark.
Add sumloop benchmark.

krono/pycket,krono/pycket,krono/pycket,samth/pycket,pycket/pycket,magnusmorton/pycket,magnusmorton/pycket,vishesh/pycket,pycket/pycket,magnusmorton/pycket,cderici/pycket,vishesh/pycket,vishesh/pycket,cderici/pycket,cderici/pycket,samth/pycket,samth/pycket,pycket/pycket