Add back button in actionbar AND Target 16 SDK onwards

By setting the navigation drawer activity as the parent to the
display article activity, We have a back button on the action bar.
I am also diplaying the company Icon there. I changed the text in
the display article activity from displayarticle (lame) to Motorindia.

Signed-off-by: Aditya Prasad <adityaprasadiskool@gmail.com>