Merge pull request #5 from ioannisstenos/master

Create cluster script with different error values
Update how_to_install_dev_env.md
Update how_to_install_dev_env.md
Update how_to_install_dev_env.md
Merge pull request #6 from MariosLogothetis/master

Dev_Environment setup instructions
Create cluster and install hadoop without configuration
Merge remote-tracking branch 'upstream/master'