Participant submission panel UI improvements

[madclam]

Add the following information to the participant submission table:

• Score shown on leaderboard
• Execution time
• Date and time submitted

[Logan-Ruf]

Added Creation Date. See #611

[ihsaan-ullah]

@Didayolo

Score shown on leaderboard

On leaderboard we could have multiple scores. Which one do we want to show here?

[Didayolo]

@ihsaan-ullah I guess there is always a column marked as "primary column", the one used for the ranking of participants. I guess it is this one that should be shown.

[ihsaan-ullah]

Execution time

@Didayolo for this i need to make more changes as execution time is not stored with the submission. I want to check with you first before starting this one

[Didayolo]

It is not overly important. We can work on this later.