Move field.php to an 'examples' folder, since it isn't part of the code. Also...

Move field.php to an 'examples' folder, since it isn't part of the code. Also add a simpler example that creates a complete form element when called by hook_widget(), similar to the way the older code works. This simple example doesn't use hook_elements(), and thus does not create re-usable widgets as the core field modules do.