* If a user doesn't belong to a company, when scoping to a company we should only show items that don't belong to a company.
* Scope tables/items to the company they belong to when fetching items for the index.
* Fix asset count to also scope to company. This fixes dashboard view
* Exempt super users from the child company check to be consistent. Fixes license count on dashboard now that we scope everything
1) Missing $admin_user in AccessoriesController::postCheckout(). Fixes#2183
2) AssetsController::postCheckin used the hardware url for the user link, not the user url
This allows for centralizing the category fetching code more and fixes
an error in asset model viewing (#2118). Also add a few translated
strings and standardize on a base of 'Select a *' for the default value
in our lists.