I hate to be the bearer of bad news, but this feature request has been declined.
-WarrenDan Duran commented
please re-consider, I agree with the original post the names are to generic. I've started adding sharepoint document librarys as tabs but still left with 'files' which leads to confustion.
Thanks to everyone who volunteered for testing the Office 365 group calendar. The TAP team will be reaching out as we are closer to being ready.