Specify branch for build status

README.md

@@ -2,7 +2,7 @@
 
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-[![Build Status](https://travis-ci.org/yyuu/pyenv.svg)](https://travis-ci.org/yyuu/pyenv)
+[![Build Status](https://travis-ci.org/yyuu/pyenv.svg?branch=master)](https://travis-ci.org/yyuu/pyenv)
 
 pyenv lets you easily switch between multiple versions of Python. It's
 simple, unobtrusive, and follows the UNIX tradition of single-purpose