The translation of '%ss' doesn't make sense

The function `on_before_render()` of the `concrete5_Controller_Dashboard_Workflow_Me` class contains the code `t('%ss', …)`, where the … may be `Page`, `File` or `User`.
Anyway, with that code, translators have to literally translate `%ss`, which doesn't make sense: only in English the plural form is composed by adding an 's' after a word (and even in English this is not always true).
My solution is to translate every case.

Another, more elegant, solution, would be to change the `/web/concrete/config/install/base/permissions.xml` file, adding a new xml attribute (let's call it `tabName`) containing the text for the tabs for each one of the `category` nodes of the `workflowprogresscategories` node. This implies we have to modify the function `importWorkflowProgressCategories()` of the `/web/concrete/core/libraries/content/importer.php` file and the `Concrete5_Model_WorkflowProgressCategory` class to manage this new `tabName` property.