Add configuration parameters to activities

[Pirvu2k]

Let the user customise the activities. For example, at the moment there is a fixed 10 second timeout on speed dating (for testing purposes only), but we should allow the user to set it to whatever value he wants. We could do this in 2 ways:

1. Either include the configuration in the game command itself: !mitra game speed_dating 20 -> sets the round time to 20
2. Or make a general-purpose map in the bot config for various properties: !mitra set speed_dating_time 20 -> sets the round time to 20

I think both approaches are good, but if we decide to implement the first one we need to find a smooth way to do it and reuse functionality as much as possible. Second one feels more natural but seems pretty general (the current config could appear when doing !mitra status )