Retry failed ssh commands. This is especially useful during system startup when the hosts may not have yet come on-line but can be useful at other points for people with flakey connections
Uniform whitespace across scala examples
Just use a loop for retries
Merge pull request #555 from holdenk/master

Retry failed ssh commands in the ec2 python script.
Merge pull request #559 from ash211/patch-example-whitespace

Uniform whitespace across scala examples
Merge branch 'master' of https://github.com/mesos/spark into master-2.10