Link Additions

[euisuny]

Some links to add:

On Homepage :

• [x] DSL (https://dsl.cis.upenn.edu/) and databases (https://dbappserv.cis.upenn.edu/home/) groups
• [x] Move Logics & Computation Links under DSL

On PLClub Schedule:

• [x] "Separately from the main PL club meeting, there is a group meeting on Wednesdays for Alur, Bastani, and Naik's groups (mailing list https://lists.seas.upenn.edu/mailman/listinfo/abn-group)"

Thanks @cdstanford for suggestions!