Decrease gov voting period form 5 days to 4 days

We have been discussing this internally for few months already. While we need few days of voting to give everyone a chance to vote, we see a need to quicker reaction when we need to release updates. Also this gives use more upgrade windows. We try to avoid lunch an upgrade from Friday to Sunday. We also do bunch of internal tests. Using 4 days voting will give use a big more flexibility. Finally, we have more proposals related to asset listing and token settings updates. This will also give use shorter to market time and hopefully provide better user experience.

CommonWealth discussion: https://commonwealth.im/umee/discussion/13088-decrease-gov-voting-period-form-5-days-to-4-days