Database related bugfixes

- Fixes the following SQL error:
[13:44:09]GAME: SQL ERROR during death reporting. Error : [Table 'ss13.death' doesn't exist]
The issue was with cyborg death logging, which was not updated properly to log into the correct table.

- Fixed the SQL schema so it properly logs deaths and the legacy_population thing (which logs how many admins and players were on every 5 minutes). If you already have a database set up and don't want to completely wipe it (Let's be honest, you really don't want to do that), look at this thread for help in updating the database properly: http://www.ss13.eu/phpbb/viewtopic.php?f=6&t=194