Merge pull request #61 from pybuilder/add_twitter

Added Twitter

Author: arcivanov

index.html

@@ -35,6 +35,9 @@ <h2>
                     frameborder="0" scrolling="0" width="110px" height="20px"></iframe>
             <iframe src="https://ghbtns.com/github-btn.html?user=pybuilder&repo=pybuilder&type=fork&count=true"
                     frameborder="0" scrolling="0" width="110px" height="20px"></iframe>
+            <a href="https://twitter.com/intent/follow?screen_name=pybuilder_">
+                <img src="https://img.shields.io/twitter/follow/pybuilder_?label=Follow%20PyBuilder&style=social"
+                     alt="Follow PyBuilder on Twitter"/></a>
             <a href="https://gitter.im/pybuilder/pybuilder">
                 <img src="https://img.shields.io/gitter/room/pybuilder/pybuilder?logo=gitter"
                      alt="PyBuilder Gitter Room"/></a>