Add heatmap to analytics page

**Is your feature request related to a problem? Please describe.**
I would like to provide a heatmap of time of day, and day of week, of when deployments happen.

**Describe the solution you'd like**
Similar to GitHubs Contributions heatmap of month/day of week. Substitute the month on the top, for the hour of the day.


**Describe alternatives you've considered**
None yet.

**Additional context**
None.

The issue names no files, tests, or entry points; start by locating the analytics page and the deployment data it uses. Define the heatmap's time-of-day and day-of-week behavior, then verify that the page displays deployment activity in a GitHub Contributions-style layout.

Written by the indexing model from the issue text.