Do serial docker pull to fix odd issue where docker was reporting layer pulled that was not
Merge pull request #49 from derekwaynecarr/serial_docker_pull

Do serial docker pull to fix docker pull issue
Increase docker pull timeout
Merge pull request #50 from derekwaynecarr/serial_docker_pull

Increase docker pull timeout
Retry docker pull in case of silent failure
Merge pull request #51 from derekwaynecarr/serial_docker_pull

Retry docker pull in case of silent failure
remove extra dirs