fixed a typo in README.

Author: agentzh

README

@@ -11,7 +11,7 @@ The bundled software components are copyrighted by the respective copyright hold
 
 The homepage for this project is http://openresty.org.
 
-For the users:
+For users:
     Visit http://openresty.org/#Download to download the latest bundle tarball, and
     follow the installation instructions in the page http://openresty.org/#Installation.