Make a Joomla 2.5 plugin that saves ''create date'' values from the frontend editing form into the database

In Joomla 2.5, the standard form for frontend-editing of articles (components/com_content/views/form/tmpl/[login to view URL]) does not provide an opportunity to change the "create date" parameter (whereas in backend, this is possible). I have already done first steps to modify the [login to view URL] in a way to show the create-date parameter in frontend. However, what is missing is a function to save data put into this field by the frontend user into the database. The task is to create a plugin that provides this function. For additional information and requirements, see the details below. ## Deliverables The plugin must work with Joomla 2.5 It should be called "Frontend-Create-Date-Access" Setting user-defined values for "created" (create date) must be possible both for new articles and for existing ones. The "[login to view URL]" with my additions (which make the create-date value appear in the form) is included in a zip-file here, and you may use it as a first step. It might, however, be necessary to check and improve it since something necesssary might be missing. (In the file, you will see my additions commented.) The plugin must be able to be installed via the usual extension manager in Joomla. This installation process should include replacing the "[login to view URL]" with the modified edit.php. Preferably the modified [login to view URL] should be placed in a way to ensure survival of a Joomla core update. (Meaning that the modified [login to view URL] should not be stored in components/com_content/views/form/tmpl/, but elsewhere, be it a template override or the plugin directory or whatever you like.)