CIMI - Add support for $expand on cloudEntryPoint

CIMI was missing $expand functionality for the cloudEntryPoint.

This pull request add the $expand functionality to cloudEntryPoint
addressing Jira DTACLOUD-502.

I have one issue I need help addressing. That is I needed to add
some "require_relative"s that I don't think should be needed to 
server/lib/cimi/service/cloud_entry_point.rb

Please don't push this just provide review feedback and suggestions
on how to avoid adding these "require_relative"s.