Add support for creating a Route for ModelRegistry http REST service, fixes #19

[dhirajsb]

Description

Added template and logic to create an OpenShift Route only if the controller is running in an OpenShift cluster.
Fixes #19

How Has This Been Tested?

Tested by setting the rest spec flag ServiceRoute to enabled in sample model registry manually to verify that Route is created.
Tested Route by using curl against the hostname created by OpenShift.

Merge criteria:

• The commits and have meaningful messages; the author will squash them after approval or will ask to merge with squash.
• Testing instructions have been added in the PR body (for PRs involving changes that are not immediately obvious).
• The developer has manually tested the changes and verified that the changes work

[dhirajsb]

This only exposes the HTTP endpoint right now, because there are issues with doing the same for gRPC. It appears that the gRPC connection needs to be a secured SSL connection for Routes, and there are issues in SSL configuration in mlmd.

[tarilabs]

looks good to me and matches my understanding of what I created manually during tests:

Thank you!