Core: Core/add link image fields

## Ready State: (Yes)

Adding a standard link field and image field to ImageX Common Fields

## Deployment Instructions

* Merge code.
* Run `drupal-org.make` for the ImageX Installkit
* Ensure the module is enabled and feature is set to default
* Clear caches with `drush cache-clear all`

## Usage/Test Instructions

* Edit a content type and go to `manage fields`
* Attempt to add an existing field
* See that field_image and field_link are available