Conflicting suggested editor CSS file name

On the WYSIWYG profile configuration, the text beneath the style list says...

A list of classes that will be provided in the "Styles" dropdown, each on a separate line. These styles should be available in your theme's editor.css as well as in your theme's main CSS file.

However, the README.txt file reads:

Themes may specify iframe-specific CSS files for use with CKEditor by including
a "ckeditor_stylesheets" key in the theme .info file.

ckeditor_stylesheets[] = css/wysiwyg.css

I recommend that we refer to this file with the same name in both locations so that people don't get confused and think that we need two different files. Patch attached that changes the README to use editor.css too.