* Added "migration of migrations" to transfer the data from the __diesel_schema_migrations table to the refinery_schema_history table
* Removed all down migrations as refinery does not support down migrations
* Changed all diesel up migrations to refinery naming format
* Added --sql-log-mode parameter to veloren-server-cli to allow SQL tracing and profiling
* Added /disconnect_all_players admin command
* Added disconnectall CLI command
* Fixes for several potential persistence-related race conditions
- get rid of old SysTimers for each system in favour of VSystem tracking
- move metrics generation from lib.rs to own system
- code cleanup
- remove time tracking in common::sys
data associated with a character, rather than individually as we were
planning to do with stats/inv/etc... This removes potential for DB locking when we deal with each individually, and we
should have plenty of room for additional writes within the transaction.
