Error: "unable to process Dockerfile: unable to parse repository info: repository name component must match:"

[Philip Rhoades]

People,

I updated docker on F22 from:

   docker-1.7.1-8.gitb6416b7.fc22.x86_64
   docker-selinux-1.7.1-8.gitb6416b7.fc22.x86_64

to the latest:

   docker-1.8.2-1.gitf1db8f2.fc22.x86_64
   docker-selinux-1.8.2-1.gitf1db8f2.fc22.x86_64

and tried doing a:

   docker build .

in an existing directory and Dockerfile that I have been using before 
and I get the error above - the regex that follows:

   "[a-z0-9]+(?:[._-][a-z0-9]+)*"

is insisting on all lower case but my previous Docker Base Image was:

   Fedora-Docker-Base-23_Alpha-20150805.x86_64.tar.xz

and I just tried:

   Fedora-Docker-Base-23_Beta-20150915.x86_64.tar.xz

with no luck either so I renamed this to:

   fedora-docker-base-23_beta-20150915.x86_64.tar.xz

and reloaded it and changed the name in the Docker file but of course 
then grabbing stuff from the repo doesn't work . .

What is going on?  Have I messed up something somehow?

Thanks,

Phil.
-- 
Philip Rhoades

PO Box 896
Cowra  NSW  2794
Australia
E-mail:  phil at pricom.com.au