[T(A)ILS-dev] doc: usb install

Hi everybody,

I just pushed some more doc in the doc-rework branch:

download.html#index4h1
→ Burn a CD or install onto a USB stick

doc/usb-install-for-windows.html
→ Installing onto a USB stick, for Windows

Reviews are welcome.

I didn't know that the Universal USB Installer of
http://www.pendrivelinux.com/ was already including an option for Tails.
Plus it works!

--
sajolida