Added Java 8 to README.md

README.md

@@ -27,7 +27,7 @@ This tutorial shows how to build Stratosphere on your own system. Please open a
 * Unix-like environment (We use Linux, Mac OS X, Cygwin)
 * git
 * Maven (at least version 3.0.4)
-* Java 6 or 7
+* Java 6, 7 or 8
 
 ```
 git clone https://github.com/stratosphere/stratosphere.git