Use H5BP server configs

Checks out a stable version of h5bp/server-configs-nginx and applies it
to the /etc/nginx folder

http://goo.gl/pBfB4W

Misc:
Adds "restart nginx" handler

Moved nginx variables to defaults yml

formatting issues

Enable better default site to drop unknown requests
Merge pull request #37 from austinpray/H5BPserverconfigs

Use H5BP server configs