hackerspace session reminder

[bingyuanng]

Is your feature request related to a problem? Please describe.
Forget gt hackerspace

Describe the solution you'd like
A reminder every Tuesday there could be hackerspace session (show link), and if there's no hackerspace session don't forget to do some work on your project too smiley

Describe alternatives you've considered
Let the admin manually post it.

Additional context
Not sure if you need DB for this. since it's recurring fixed time.