Added LastAccessed time field and KnownIPs field to the user database.  This resulted in some changes everywhere, such as new logic with default groups.  Apparently, somehow, the ip based stuff worked even though no ips were set to properly grab the user group.  The wrong group was being assigned to new users resulting in a player with 0 permissions.  This is now fixed.
Merge pull request #530 from Olink/general-devel

Added LastAccessed time field and KnownIPs field to the user database. Note: extent of testing was starting TShock again, so may have broken something important (e.g. stat tracking)