readme: simplify the process of manually creating the `debian-sys-maint` user
readme: fix link to "Creating User and Database at Launch" section
dockerfile: switch back to the ubuntu:14.04 base image
readme: added "Contributing" section
dockerfile: upgrade to sameersbn/ubuntu:14.04.20141026 base image
readme: specify image version in administrative login command
Merge pull request #1 from sameersbn/master

Update fork with source repository