Update README.md

Author: chronolaw

README.md

@@ -9,3 +9,15 @@ Requirements
 * Linux or other UNIX like
 * C++11(gcc 4.6 or later)
 * Boost(1.57 or later)
+
+Usage
+=====
+At first, we must patch nginx/auto/make to enable g++ compiler and C++11.
+
+Then configure nginx with:
+~~~~
+./configure --add-module=path/to/ngxpp	\	  # ngx cpp module
+			   --add-module=xxxx			            # other modules
+make
+~~~~
+