Minimum Commission 2.5%

With the recent attacks a lot of discussion has been had about different elements that can be done to harden security on the chain.\n\nOne element was to improve infrastructure that validators run on, be this barebone or hosted it increases the cost to do so and keep doing so to secure the chain.\n\n0% commission makes it difficult to allow this to happen while being competitive with other validators. A recent 5% prop was voted down due to decreasing the delta for DynComm too much, as such 2.5% is being proposed as a happy medium