Add asset management permissions

[jmcameron]

Add special permission(s) for assets management and add bh-has-permission as needed on the various registries and create/add modals, as necessary.

The basic page permissions allow control of who can access the various pages under the Assets management menu. That is probably most of what is needed.

However, it might be prudent to add some special action menu permissions (Administration > User Management > user > Actions) which would require special permissions for doing things like editing a Required Inventory Scan.

Perhaps it will become clearer what permissions are needed in practice once we get more experience in Asset management in production sites.

Add action permissions for the "Add Asset Scan" for the action menus in the Assets Scans Registry since it does not require a physical barcode scan to scan an item and could be abused to indicate the presence of an asset that has been lost or stolen.