Closes #1733

Now semantic-release tags without `v` prefix so updating post-push hook.

We need to parse $IMAGE_NAME because $CACHE_TAG is broken on Docker Hub post_push

Docker's build process doesn't allow you to ADD or COPY files from outside the directory tree. e.g. `ADD ../package.json .` is forbidden. The only option I can see is to move it and `hooks` back into the project root.