Allow disable htmlparser plugin

lib/loader/pluginLoader.js

@@ -287,7 +287,7 @@
                     console.error("Plugin '" + pluginDeclaration.id + "' overridden by", pluginPath);
                     delete plugins[pluginDeclaration.id]
                 } else {
-                    console.error("Duplicate plugin id (filename)", pluginPath);
+                    console.error("Duplicate plugin id ignored (filename)", pluginPath);
                     return;
                 }
             }

lib/plugins/system/htmlparser/__allowHtmlparser.js

@@ -0,0 +1,15 @@
+
+export default {
+
+    provides: [
+        // Run for all who requests htmlparser or meta.
+        'htmlparser',
+        '__allowHtmlparser'
+    ],
+
+    getData: function() {
+        return {
+            __allowHtmlparser: true
+        };
+    }
+};

lib/plugins/system/htmlparser/htmlparser.js

@@ -16,7 +16,7 @@ export default {
         '__statusCode'
     ],
 
-    getData: function(url, whitelistRecord, options, __noCachedHtmlparserFallback, cb) {
+    getData: function(url, whitelistRecord, options, __noCachedHtmlparserFallback, __allowHtmlparser, cb) {
 
         var options2 = {...options, ...{
             followRedirect: !!options.followHTTPRedirect,