Portfolio & Reflection-Question Feedback Navigation

As a user can't see if a new comment was made after he last opened the accordion the idea is the following:

• track last click on entry in DB.

Steps:

• if new comment/entry is made => add timestamp of creation to tracking DB table
• if "last clicked" timestamp is before the new comment timestamp: show Neuer Kommentar/Beitrag on entry card
• onClick by user: refresh onclick timestamp in database

added Todo Martin Masterarbeit label

mentioned in issue #249 (closed)