Implement basic permission check for message commands

src/main/java/wtf/beatrice/hidekobot/objects/commands/MessageCommand.java

@@ -1,8 +1,11 @@
 package wtf.beatrice.hidekobot.objects.commands;
 
+import net.dv8tion.jda.api.Permission;
 import net.dv8tion.jda.api.events.message.MessageReceivedEvent;
+import org.jetbrains.annotations.Nullable;
 
 import java.util.LinkedList;
+import java.util.List;
 
 public interface MessageCommand
 {
@@ -16,10 +19,19 @@ public interface MessageCommand
      */
     LinkedList<String> getCommandLabels();
 
+    /**
+     * A list of permissions required to run the command. This is preferred to checking them on your own
+     * as the message listener handles it more homogeneously.
+     *
+     * @return the list of required permissions.
+     */
+    @Nullable
+    List<Permission> getPermissions();
+
     /**
      * Say if this command does its own text parsing, and tell the message listener if it should automatically
      * split all arguments in separate entries of an array, or pass everything as the first entry of that array.
-     *
+     * <p>
      * This is better instead of getting the message contents from the event, because the message listener will
      * still strip the bot prefix and command name from the args, but leave the rest untouched.
      *
@@ -30,7 +42,6 @@ public interface MessageCommand
     /**
      * Run the command logic by parsing the event and replying accordingly.
      *
-     *
      * @param event the received message event. It should not be used for parsing message contents data as
      *              the arguments already account for it in a better way.
      *