Hotfix: tweak to make imported entities have author as user 1

## Ready State: Yes

Enhancement from work related to https://imagex.atlassian.net/browse/LDC-311

If the entity to be created supports "author" property & theres no mapping to that field the author value defaults to be user 1.

## Requirements & Dependencies

None

## Deployment Instructions

* Merge code.
* Enable module `imagex_aggregator`
* Clear caches with `drush cache-clear all`

## Usage/Test Instructions

* Go to /admin/config/services/aggregator & add a feed, just map to a node type & fields, title -> title
* Back on /admin/config/services/aggregator, click "Update Items" on feed, ensure "ITEMS" column updates & that the ensure a related node (of the type selected) has been created for each feed item & the author of each node is user 1