Add the X-Content-Type-Options nosniff HTTP header
Enable the X-XSS-Protection HTTP header
Add X-Frame-Options SAMEORIGIN protection
Prevent a variety of backup and config files from being served
s/extension/extensions/
Prevent backups and configs from being served at the content URL as well
Merge pull request #2 from washingtonstateuniversity/nginx-security-directives

Add a handful of initial security directives for Nginx