Close DB on shutdown

Apparently, we can’t trust the library to handle this, as their hook
seems to fail.

src/main/kotlin/moe/kageru/kagebot/Kagebot.kt

@@ -5,6 +5,7 @@ import moe.kageru.kagebot.config.Config
 import moe.kageru.kagebot.config.ConfigParser
 import moe.kageru.kagebot.config.RawConfig
 import moe.kageru.kagebot.cron.CronD
+import moe.kageru.kagebot.persistence.Dao
 import org.javacord.api.DiscordApiBuilder
 import org.javacord.api.event.message.MessageCreateEvent
 import java.io.File
@@ -44,6 +45,7 @@ object Kagebot {
         }
         Runtime.getRuntime().addShutdownHook(Thread {
             Log.info("Bot has been interrupted. Shutting down.")
+            Dao.close()
             Globals.api.disconnect()
         })
         Log.info("kagebot Mk II running")

src/main/kotlin/moe/kageru/kagebot/command/MessageRedirect.kt

@@ -35,6 +35,7 @@ internal class MessageRedirect(rawRedirect: RawRedirect) {
         }
 
         if (MessageUtil.sendEmbed(target, embed).failed()) {
+            target.sendMessage("Error: could not redirect message.")
             Log.warn("Could not redirect message to channel $target")
         }
     }

src/main/kotlin/moe/kageru/kagebot/persistence/Dao.kt

@@ -11,6 +11,8 @@ object Dao {
         prisoners[releaseTime] = roles.toLongArray()
     }
 
+    fun close() = db.close()
+
     fun getAllTimeouts() = prisoners.keys
 
     fun deleteTimeout(releaseTime: Long): LongArray {