Currently when bulk-awarding a badge that can be granted multiple times, users in the CSV file are granted the badge once no matter how many times they're listed in the file and only if they don't have the badge already.
This PR adds a new option to the Badge Bulk Award feature so that it's possible to grant users a badge even if they already have the badge and as many times as they appear in the CSV file.
* UI: Mass grant a badge from the admin ui
* Send the uploaded CSV and badge ID to the backend
* Read the CSV and grant badge in batches
* UX: Communicate the result to the user
* Don't award if badge is disabled
* Create a 'send_notification' method to remove duplicated code, slightly shrink badge image. Replace router transition with href.
* Dynamically discover current route