Override toString() method in Command

Overriding the toString() method provides more human-readable feedback
when a problem occurs, including the version of the plugin if
applicable.

src/main/java/org/bukkit/command/Command.java

@@ -350,4 +350,9 @@ public abstract class Command {
             }
         }
     }
+
+    @Override
+    public String toString() {
+        return getClass().getName() + '(' + name + ')';
+    }
 }

src/main/java/org/bukkit/command/PluginCommand.java

@@ -144,4 +144,12 @@ public final class PluginCommand extends Command implements PluginIdentifiableCo
         }
         return completions;
     }
+
+    @Override
+    public String toString() {
+        StringBuilder stringBuilder = new StringBuilder(super.toString());
+        stringBuilder.deleteCharAt(stringBuilder.length() - 1);
+        stringBuilder.append(", ").append(owningPlugin.getDescription().getFullName()).append(')');
+        return stringBuilder.toString();
+    }
 }