remove duplicate info from linuxserver/baseimage

Dockerfile

@@ -5,9 +5,6 @@ RUN rm -rf /etc/service/sshd /etc/my_init.d/00_regen_ssh_host_keys.sh
 MAINTAINER Mark Burford <sparklyballs@gmail.com>
 
 # Set correct environment variables
-ENV DEBIAN_FRONTEND noninteractive 
-ENV HOME /root 
-ENV TERM screen
 ENV LANG en_US.UTF-8 
 ENV LANGUAGE en_US:en 
 ENV LC_ALL en_US.UTF-8