worker class gevent processes concurrent requests

with no worker class specified, it is using 'sync' which is essentially just those four forked processes, which in python means: slower than a single process. gevent will give better performance.
fixed worker-class, added preload

for gunicorn apps in production, preload should be true. 
Merge branch 'patch-1' of https://github.com/sp1d3rx/FrameworkBenchmarks into sp1d3rx-patch-1
small error in flask setup.py with worker-class