Shout Vote (Map Voting)

Fixes, changes and additions for ShoutVote 1.5.4

If you are updating: You don't need to update your sh_shoutconfig.lua file, so you can keep all your custom configs and settings!

Changelog:

1. [FIX] Fixed UserGroupPower not working correctly when Shout Power was disabled.
2. [FIX] Fixed rare error when ShowPercentages was disabled. (Thanks ogt.bungle)
3. [CHANGE] Updated the config file/User Guide to more clearly explain how UserGroupPower works when both Shout Power is enabled and disabled.
4. [CHANGE] Updated the config file/User Guide to more clearly explain that when you use SHOUT.Settings.MapPrefixes to specify your own maps/prefixes you must also change SHOUT.Settings.AutoSetPrefixes = false or Shout Vote will continue to select maps based on the current gamemode.