Update deploy/nginx.conf template from production

Remove SSL config as SSL is terminated at load balancer

Hardcode X-forwarded-Protocol header to https as we have
a global http->https redirect at the load balancer

Remove server_name and use this as default config

Add basic auth config and exception for the admin

Fix protected uploads
Templatize proxy_pass in admin basic auth exception
Merge pull request #96 from jgmize/nginx-template

Update deploy/nginx.conf template from production