Allow comma-separated list of DBs to create
Update README.md

Change (depracated) `-link` to `--link`.
Update Dockerfile

Prevent creation of unnecessary Docker cache images (the ones that only echo something).
Merge pull request #11 from lightoze/master

Allow comma-separated list of DBs to create
Merge pull request #12 from mauvm/patch-1

Update README.md
Merge pull request #14 from mauvm/patch-2

Update Dockerfile
Fix syntax
Merge pull request #15 from parrish/broken_syntax

Fix syntax
Merge pull request #16 from zheli/master

added log directory as volume
Use new command line flags.  Using single hyphen is deprecated.
Adjustments for running with the phusion/baseimage.
Correct env variables in README.md (#18)
Remove fetching the postgresql keys.  This step tends to fail when being built at docker.io.