Merge branch 'patch-13' into 'master'

Update Nginx definition

Update Nginx definition cc @ChadMalchow 

See merge request !44

source/glossary/index.html.md

@@ -299,7 +299,7 @@ Prominent examples include:
 ### Nginx
-*** Needs definition here
+(pronounced "engine x") is a web server. It can act as a reverse proxy server for HTTP, HTTPS, SMTP, POP3, and IMAP protocols, as well as a load balancer and an HTTP cache.
 ### oAuth