Optimize course time display group by day and times

[iphadey]

Group and splitting course day and time

[thdebay]

Hello @iphadey and thank you for this great PR. It works great. I only have one concern before merging it. The outputs for these two -hypothetical- situations would be identical:

• Mon 9-10 and Fri 9-10
• Mon to Fri 9-10

Do you think it's feasible to modify the output of the first one to be Mon | Fri 9-10 (the second situation would still give Mon - Fri 9-10)