Update dockerimages.md

The container ID in the text didn't match the container ID from the figure above it.
Fixed a minor docs issue in a Dockerfile Example

The Dockerfile Instruction to create the .vnc directory results in a failure :
-storepasswd failed for file: /root/.vnc/passwd

Signed-off-by: Madhu Venugopal <madhu@socketplane.io>
Merge pull request #8649 from mavenugo/master

Fixed a minor docs issue in a Dockerfile Example
Merge pull request #8622 from Coaxial/patch-1

Update dockerimages.md