ssh_client fixture, updated/expanded ssh utils

- Needs a change to credentials.yaml, see credentials.yaml.template
- Tests!
selenium fixture now supports navigation fixtures
Merge pull request #79 from seandst/distributed-testing-selenium-shenanigans

selenium fixture now supports navigation fixtures
Merge pull request #83 from seandst/distributed-testing-ssh-shenanigans

ssh_client fixture, updated/expanded ssh utils
Add support for scp
Tell ssh client not to look for keys
Fix ssh_client_run_command test Assert.contains.
Merge pull request #91 from bcrochet/add-scp

Add support for scp
--amend
--amend
spacing issues
spacing issues
spacing issues