Adds methods for registering a command

src/main/java/net/knarcraft/knarlib/plugin/ConfigCommentPlugin.java

@@ -1,9 +1,15 @@
 package net.knarcraft.knarlib.plugin;
 
 import net.knarcraft.knarlib.config.StargateYamlConfiguration;
+import org.bukkit.command.CommandExecutor;
+import org.bukkit.command.PluginCommand;
+import org.bukkit.command.TabExecutor;
 import org.bukkit.configuration.file.FileConfiguration;
 import org.bukkit.plugin.java.JavaPlugin;
 import org.jetbrains.annotations.NotNull;
+import org.jetbrains.annotations.Nullable;
+
+import java.util.logging.Level;
 
 /**
  * A plugin that uses a Stargate YAML configuration in order to retain all configuration comments
@@ -35,4 +41,35 @@ public abstract class ConfigCommentPlugin extends JavaPlugin {
         return this.configuration;
     }
 
+    /**
+     * Registers a command
+     *
+     * @param commandName <p>The name of the command to register</p>
+     * @param executor    <p>The executor to register for the command</p>
+     */
+    private void registerCommand(@NotNull String commandName, @NotNull CommandExecutor executor) {
+        registerCommand(commandName, executor, null);
+    }
+
+    /**
+     * Registers a command
+     *
+     * @param commandName     <p>The name of the command to register</p>
+     * @param commandExecutor <p>The command executor to register for the command</p>
+     * @param tabExecutor     <p>The tab executor to register for the command</p>
+     */
+    @SuppressWarnings("SameParameterValue")
+    private void registerCommand(@NotNull String commandName, @NotNull CommandExecutor commandExecutor,
+                                 @Nullable TabExecutor tabExecutor) {
+        PluginCommand pluginCommand = this.getCommand(commandName);
+        if (pluginCommand != null) {
+            pluginCommand.setExecutor(commandExecutor);
+            if (tabExecutor != null) {
+                pluginCommand.setTabCompleter(tabExecutor);
+            }
+        } else {
+            getLogger().log(Level.SEVERE, "Failed to register command " + commandName);
+        }
+    }
+
 }