Remove the "still maintained" banner.

This is done in anticipation of their discontinuing service.
diff --git a/README.mdown b/README.mdown
index 45b8965..c7238e6 100644
--- a/README.mdown
+++ b/README.mdown
@@ -1,5 +1,6 @@
-git-flow ![Project status](http://stillmaintained.com/nvie/gitflow.png)
+git-flow
 ========
+
 A collection of Git extensions to provide high-level repository operations
 for Vincent Driessen's [branching model](http://nvie.com/git-model "original
 blog post").