Core: submodule for featured content panel page

## Ready State: Yes

This pull request is related to the following JIRA tickets: https://imagex.atlassian.net/browse/LDC-157
and PR: https://github.com/imagex/imagex_installkit/pull/43

## Requirements & Dependencies

* This new module requires imagex_featured_content, features, imagex_blog_featured

## Deployment Instructions

* Merge code.

## Usage/Test Instructions

* ensure panel page exists with view panel for featured content.

NOTE:  view currently includes image field, but may need to be removed or logic added to handle content types without images.