Give an easy way for a person to set up a report of past OSS contributions

[damithc]

Usage: A user (e.g., a student) setting up an online report of their open-source coding work.

Steps:

1. Forks a provided repo (e.g., https://github.com/reposense/code-report) to own GitHub account
2. Updates a config file in the fork to specify repos contributed to, author names used in each repo
3. After committing the change, and CI run, the report is available for viewing (and can be linked from their resume, home page etc.)

A further optimization is to show each ramp for the time period in which there are relevant commits. i.e., in the ramp chart below, show the part in the red box only.

This means each ramp chart will have its own timeline, and we'll have to show the timeline for each ramp chart.

[ckcherry23]

Related to #1431