Feature: LDC-158 - tweaked view to entity rows, added exposed operator f...

## Ready State: Yes

Relates to jira task: https://imagex.atlassian.net/browse/LDC-158

2 additions to the new imagex_blog view:
* Change the row render to entity
* Exposed the filter operator to allow tags to be excluded as well as include ie. show all blog posts minus "Linux Foundation"

## Requirements & Dependencies

None

## Deployment Instructions

* Merge code.
* Enable module ` imagex_blog`
* Clear caches with `drush cache-clear all`

## Usage/Test Instructions

* Create some blog posts, tag them in the tags field
* Using panelizer add a new "Blog List Pane" and ensure:
 *  you can filter blog posts by a certain tag
 * you can exclude certain blog posts if they have a tag or tags