Untranslatable texts in some files

I am not sure if it should be called a bug, but I found some texts were hard coded and not translatable.

• Slides content: (admin/settings.php, line 360)
• Columns content: (admin/settings.php, line 456)
• all the texts in includes/widgets.php
• empty text in admin/customizer.php, line 36

And some suggestions to change texts for better translations:

• View all posts by => View all posts by %s (single.php, line 40)
• Posted on => Posted on %s (admin/admin-functions.php, line 291)
• Permalink to => Perma link to %s (includes/themes-loop.php, line 274)
• “top” and “left” should look better if it is placed before the input field.

(admin/settings.php, line 163)

The most of above applies to Nirvana, too.
These are not much problems actually, but it would help people who are not so familiar with English if you make changes.