Add basic dfs/mapred include/exclude host file support
update HDFS over Lustre information to include information on rebalancing blocks if increasing node size ; add hadoop-rebalance-hdfs-over-lustre-if-increasing-nodes-script.sh
make exclude file, it is empty by default
add convenience script hadoop-create-files.sh
Support ability to decomission nodes w/ hadoop-hdfs-over-lustre-nodes-decomission-script.sh

export new environment variable HADOOP_SLAVE_COUNT
update NEWS with changes
Add new convenience script hadoop-list-files-script.sh