Service not starting on Ubuntu 15.04

I posted to stackoverflow about my problem upgrading from Ubuntu 14.04 to Ubuntu 15.04: http://stackoverflow.com/questions/33306475/ubuntu-15-04-postgresql-doesnt-start

Tl;dr: postgresql service does not start properly when installed as a package using cloud-init.

And I can't figure out if I am doing something wrong, if the AMI is no good, if the package has problems, ... I reckon I cannot be the first person to use Postgres on Ubuntu Vivid, but I have been hammering my head against the wall with this for hours.

Any help greatly appreciated!

Regards,

Lasse