check whether file/directory exists
Merge pull request #64 from mengxr/copy-dir

check whether file/directory exists in copy-dir
Allow attaching up to 5 EBS volumes.
Code review feedback.
Merge pull request #65 from rxin/v3-ebs

Allow attaching up to 5 EBS volumes.
Support up to 8 EBS volumes.
Alias vol3 vol.
Merge pull request #66 from rxin/v3-ebs

Support up to 8 EBS volumes.
HOTFIX: Adding Spark 1.1.0
remove wrong extra '*)'

remove wrong extra '*)'
Merge pull request #67 from dselivanov/v3

HOT-FIX remove wrong extra '*)'
Merge remote-tracking branch 'mesos/v3' into v3