Cut down the size of the Docker::Container#export VCR.
Cut down the size of the Docker::Container#export VCR.

Instead of running the container with a `ls` command, I changed the command to `rm -rf / --no-preserve-root`. This cut down the size considerably, but the file is still ~150M.

swipely/docker-api,ComputeStacks/docker-api,ably-forks/docker-api,moritzheiber/docker-api,someara/docker-api,njd5475/docker-api,BWITS/docker-api,ComputeStacks/docker-api,alexandrz/docker-api,chasebolt/docker-api,molisoft/docker-api,Ye-Yong-Chi/docker-api,aratak/docker-api,someara/docker-api,jefflaplante/docker-api,pwnall/docker-api,moritzheiber/docker-api,swipely/docker-api,chasebolt/docker-api