Revert "README: Display 4.3.4 Travis badge instead of master's"

This reverts commit 5ca5d9fe44.

Wrong branch, I'm sorry.

README.md

@@ -1,6 +1,6 @@
 # ![logo](http://www.trinitycore.org/f/public/style_images/1_trinitycore.png) TrinityCore
 
-[![Build Status](https://travis-ci.org/TrinityCore/TrinityCore.svg?branch=4.3.4)](https://travis-ci.org/TrinityCore/TrinityCore)
+[![Build Status](https://travis-ci.org/TrinityCore/TrinityCore.svg?branch=master)](https://travis-ci.org/TrinityCore/TrinityCore)
 [![Coverity Scan Build Status](https://scan.coverity.com/projects/435/badge.svg)](https://scan.coverity.com/projects/435)
 
 ## Introduction