set nginx to 50mb limit which is upper side of what ShareLaTeX can handle

server-ce/nginx/nginx.conf

@@ -41,6 +41,8 @@ http {
 	gzip on;
 	gzip_disable "msie6";
 
+	client_max_body_size 50m;
+
 	# gzip_vary on;
 	# gzip_proxied any;
 	# gzip_comp_level 6;