New versions of Docker will not start in OSX using the cmd in these instructions as /etc/localtime cannot be mounted.
The change provides an alternate command that does work.
`docker run --rm -e TZ=`ls -la /etc/localtime | cut -d/ -f8-9` -v `pwd`/config.json:/freqtrade/config.json -it freqtrade`
More info is in this thread:
https://github.com/docker/for-mac/issues/2396