fix links in plugin loading

ygopro-server.coffee

@@ -3742,5 +3742,5 @@ if not fs.existsSync('./plugins')
 
 plugin_list = fs.readdirSync("./plugins")
 for plugin_filename in plugin_list
-  plugin_path = "./plugins/" + plugin_filename
+  plugin_path = process.cwd() + "/plugins/" + plugin_filename
   require(plugin_path)

ygopro-server.js

@@ -4829,7 +4829,7 @@
 
   for (m = 0, len2 = plugin_list.length; m < len2; m++) {
     plugin_filename = plugin_list[m];
-    plugin_path = "./plugins/" + plugin_filename;
+    plugin_path = process.cwd() + "/plugins/" + plugin_filename;
     require(plugin_path);
   }