update Dockerfile

don't use more prefix for java version since it's unmaintanable if Ubuntu repository is not mirrored.

Author: mikefaille

2.6.0/Dockerfile

@@ -5,7 +5,7 @@ FROM ubuntu:14.04
 # JAVA
 ####################
 
-ENV JAVA_VERSION	7u79
+ENV JAVA_VERSION	7 # don't use more prefix since it's unmaintanable if Ubuntu repository is not mirrored.
 ENV JAVA_HOME		/usr/lib/jvm/java-7-openjdk-amd64
 
 RUN apt-get update && \