Merge pull request #11 from ioannisstenos/master

Create cluster, install hadoop,abort on errors,correct loggings.
Update create_cluster.py
Update create_cluster.py
Merge pull request #12 from ioannisstenos/master

Destroy cluster, improve readability
Merge pull request #13 from MariosLogothetis/master

Update How_to_run_script.md
Merge branch 'master' of https://github.com/ioannisstenos/e-science into ioannisstenos-master
Merge branch 'ioannisstenos-master'
update devenv
Merge pull request #16 from ioannisstenos/master

create_cluster, changed master fqdn with public ip to solve ssh.connect issue in ~okeanos VM
update creat cluster ssh with ipv4
Merge pull request #17 from ioannisstenos/master

create Hadoop cluster with Ansible playbook
sync repos
Merge branch 'master' of http://github.com/grnet/e-science
creat yarn cluster
Merge branch 'master' of https://github.com/nvrionis/e-science
create light webserver with Django, Celery and PostgreSQL