Added an iPhone presenter mode

Only worked up the portrait mode. Landscape mode is passable.

This allows the presenter to view notes, to tap and swipe, use the menu
to choose a slide, etc. from the phone.
Cleaned up presenter follow mode a bit

Now the remote properly switches slides on the presenter deck.
Style improvements

The slide now fills the available area
The slide source won't push the update button off
Fits on both iPhone 5 and iPhone 4 screens.
Allow remote tracking to be disabled

Adds a toggle to presenter mode that allows the presenter to disable
tracking of remote presenters.
Cleaned up styling a bit more.
Added an iPhone viewing mode, non presenter
Comment out landscape until it works
Merge pull request #46 from binford2k/iphone_presenter_mode

Added an iPhone presenter mode