readme update [skip ci]

Author: chronolaw

README.md

@@ -5,7 +5,6 @@ ngx_cpp_dev
 Nginx cpp development kit, with the power of C++11 and Boost Library.
 
 [![Build Status](https://travis-ci.org/chronolaw/ngx_cpp_dev.svg?branch=master)](https://travis-ci.org/chronolaw/ngx_cpp_dev)
-[![Waffle.io - Columns and their card count](https://badge.waffle.io/chronolaw/ngx_cpp_dev.svg?columns=To%20Do)](https://waffle.io/chronolaw/ngx_cpp_dev)
 
 Table of Contents
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