Typo's in some docker run example commands

[halr9000]

From https://github.com/splunk/docker-splunk/blob/master/enterprise/README.md:

docker run --name splunk --hostname splunk -p 8000:8000 -d -e "SPLUNK_START_ARGS=--accept-license"

This command is missing an image name and clearly won't work. If you add an image name, it's still broken. Repro:

$ docker run --name splunk --hostname splunk -p 8000:8000 -d -e "SPLUNK_START_ARGS=--accept-license"
"docker run" requires at least 1 argument(s).
See 'docker run --help'.

Usage:  docker run [OPTIONS] IMAGE [COMMAND] [ARG...]

Run a command in a new container
$ docker run --name splunk --hostname splunk -p 8000:8000 -d -e "SPLUNK_START_ARGS=--accept-license" splunk/splunk
2d45302f44756753383c8a7953ef8b05c69f089dc81d1501939fe2112760e122

working on PR