Set up connection pool and enforce usage of it

Attempt to initialize connection pool on startup until a timeout.

config.yaml

@@ -165,7 +165,6 @@ server:
     DB_URL: "jdbc:mysql://localhost:3306/cosmic"
     DB_USER: "cosmic_server"
     DB_PASS: "snailshell"
-    DB_CONNECTION_POOL: true        #Installs a connection pool to hub DB connections. Set false to default.
 
     #Login Configuration
     WORLDS: 1                           #Initial number of worlds on the server.