Feature: remove time data

This feature request is to allow the deletion of timers from the reports interface.

Seeing as each timer takes up so little space it wouldn't make sense to simply add a delete button next to every timer.

One possible implementation would be to add an edit button (either on a day or an report period) which would expose an interface optimized for managing time records

Start at the reports interface and trace how timers and time records are displayed and stored. The issue does not name files or tests, so first determine the relevant entry points and how deletion should work for a day or report period. Done means reports provide an interface for removing selected timer data without requiring a delete control beside every timer.

Written by the indexing model from the issue text.