Silence PHP warnings from disk_free_space(). disk_free_space() will produce a warning in error conditions in addition to returning false, this includes a case where the bytes free is greater than PHP_INT_MAX (which is a error condition we don't need to check).
See #25576, #22704


git-svn-id: http://develop.svn.wordpress.org/trunk@25831 602fd350-edb4-49c9-b593-d223f7449a82
Update the text for the about page, so translators can get started. Design is in flux.

props nacin, markjaquith, jorbin, jenmylo.
see #25603.


git-svn-id: http://develop.svn.wordpress.org/trunk@25832 602fd350-edb4-49c9-b593-d223f7449a82
Check if background core updates are supported on about.php.

see #25603, #22704.


git-svn-id: http://develop.svn.wordpress.org/trunk@25833 602fd350-edb4-49c9-b593-d223f7449a82
Remove redundant code. see #25603, #22704, [25833].


git-svn-id: http://develop.svn.wordpress.org/trunk@25834 602fd350-edb4-49c9-b593-d223f7449a82
In automatic background updates, standardize on 'update'.

New, final filter names:
 * auto_update_{$type} (plugin, theme, core, language)
 * automatic_updates_is_vcs_checkout
 * automatic_updates_disabled

New class name is WP_Automatic_Updater. Method names include update() and should_update().

see #22704.


git-svn-id: http://develop.svn.wordpress.org/trunk@25835 602fd350-edb4-49c9-b593-d223f7449a82
set_current_screen() is now unnecessary in Automatic_Upgrader_Skin, which is good because it breaks things in the network admin.

fixes #25622.


git-svn-id: http://develop.svn.wordpress.org/trunk@25836 602fd350-edb4-49c9-b593-d223f7449a82