[SPARK-1055] fix the SCALA_VERSION and SPARK_VERSION in docker file

As reported in https://spark-project.atlassian.net/browse/SPARK-1055

"The used Spark version in the .../base/Dockerfile is stale on 0.8.1 and should be updated to 0.9.x to match the release."

Author: CodingCat <zhunansjtu@gmail.com>
Author: Nan Zhu <CodingCat@users.noreply.github.com>

Closes #634 from CodingCat/SPARK-1055 and squashes the following commits:

cb7330e [Nan Zhu] Update Dockerfile
adf8259 [CodingCat] fix the SCALA_VERSION and SPARK_VERSION in docker file

docker/spark-test/base/Dockerfile

@@ -25,8 +25,7 @@ RUN apt-get update
 # install a few other useful packages plus Open Jdk 7
 RUN apt-get install -y less openjdk-7-jre-headless net-tools vim-tiny sudo openssh-server
 
-ENV SCALA_VERSION 2.9.3
-ENV SPARK_VERSION 0.8.1
+ENV SCALA_VERSION 2.10.3
 ENV CDH_VERSION cdh4
 ENV SCALA_HOME /opt/scala-$SCALA_VERSION
 ENV SPARK_HOME /opt/spark