Adds an option for disabling startup fixes

Also fixes configuration default values not being used when the option is missing from the configuration file.

src/main/java/net/knarcraft/stargate/config/ConfigOption.java

@@ -66,6 +66,11 @@ public enum ConfigOption {
      */
     DESTROYED_BY_EXPLOSION("gates.integrity.destroyedByExplosion", "Whether stargates should be destroyed by explosions", false),
 
+    /**
+     * Whether to fix incorrect signs, buttons or openings during startup
+     */
+    APPLY_STARTUP_FIXES("gates.integrity.applyStartupFixes", "Whether Stargates should fix incorrect signs, buttons or openings during startup", true),
+
     /**
      * Whether to verify each portal's gate layout after each load
      */