Add robustness on SSH connections in the integration testing
Add robustness on SSH connections in the integration testing

The concourse tasks will retry each SCP command up to five times until
it succeeds. It will also time out SCPing over the s3cli binary at three
minutes and try again.

[#109979784](https://www.pivotaltracker.com/story/show/109979784)

Signed-off-by: Luke Woydziak <5ec47d3d6d41d8ebc18a534604a07e736a0a4783@emc.com>

pivotal-golang/s3cli,pivotal-golang/s3cli,pivotal-golang/s3cli,pivotal-golang/s3cli