Issue 3410 styling updates

@jedp - tag, you're it!

* Add a Persona watermark next to email addresses in the email picker
* Update the "submit" button style
* Give the buttons in "Is this your computer" more space
* Shrink the TOS/PP text by 1 pt.
* Update the :focus highlight on an input element
* Fix blue cancel button on Android 2.2/2.3 native browser.


This can be seen on all-together-now.