Update for 37-13

Update for NWNEE 37-13.  Updated NWNxEE.  Full compile.

_module/nss/nwnx_core.nss

@@ -0,0 +1,21 @@
+/// @addtogroup nwnx NWNX
+/// @brief Core NWNX Functions.
+/// @{
+/// @file nwnx_core.nss
+
+const string NWNX_Core = "NWNX_Core"; ///< @private
+
+/// @brief Determines if the given plugin exists and is enabled.
+/// @param sPlugin The name of the plugin to check. This is the case sensitive plugin name as used by NWNXCall
+/// @note Example usage: NWNX_PluginExists("NWNX_Creature");
+/// @return TRUE if the plugin exists and is enabled, otherwise FALSE.
+int NWNX_Core_PluginExists(string sPlugin);
+
+/// @}
+
+int NWNX_Core_PluginExists(string sPlugin)
+{
+    NWNXPushString(sPlugin);
+    NWNXCall(NWNX_Core, "PluginExists");
+    return NWNXPopInt();
+}