Begin checked efforts

* Restrict settings page to admins only
* Remove unused styles/scripts methods
* Display chosen checkbox, radio, or select values on edit page
* Display chosen checkbox, radio, or select options on bulk and quick edit screens
Remove usused CSS file
Remove CSS file
Capture non-CBQE *_custom_column content
Youtube shortcode correction
Review youtube shortcode
Simplify JavaScript script bulk/quick

* Enable radio and select pre-setting for Quick Edit
* Enable radio and select setting for Bulk Edit
* Simplify JavaScript script bulk/quick
Add action hook references
Compatibility updates

* Account for deprecated manage_edit-${post_type}_columns
* Initialize loading later
* Link to example
Enable checkboxes

* Handle checkbox presetting for quick edit
* Handle checkbox saving for bulk edit
Redo screenshots
Correct links