Add elog_message native (#451)

* elog_message

Like "log_message". Logs a message to the current server log file, however the messages sent are also sent to all plugins and can be hooked using "register_logevent".

* Update amxmodx.cpp

* Update Editor.sci

* Update UnitfrmMain.dfm

plugins/include/amxmodx.inc

@@ -1288,6 +1288,19 @@ native log_amx(const string[], any:...);
  */
 native log_message(const message[], any:...);
 
+/**
+ * Logs a message hookable by plugins to the current server log file.
+ *
+ * @note The log will include a timestamp with the message.
+ * @note The message can be hooked using "register_logevent".
+ *
+ * @param string    Formatting rules
+ * @param ...       Variable number of formatting parameters
+ *
+ * @return          Number of printed characters
+ */
+native elog_message(const message[], any:...);
+
 /**
  * Logs a message to the specified file
  *