Weigh ins included in average shaded different color

[chiptopher]

Feature Request

Make it so that the weigh ins on the dashboard are shaded darker when they're included in calculating the rolling average.

Optional user story format:

Context

Since the rolling average is calculated as an average of all weigh ins in the last X number of hours, depending on when you view it there could be more than expected.

For example, imagine you have your average set to three days. If you put a weigh in late on Monday, it may still be included in the average calculation if you check early Thursday morning.

Acceptance Criteria

The last X number of hours worth of weigh ins are shaded darker.