Show and hide controls with mousemove / Select 'Off' in subtitles menu by default

Whoops, I intended these to be separate but it looks like all of my updates have been combined into one pull request now. Here's some info, I hope these are helpful!

1) Show and hide controls with mousemove (src/controls.js, src/lib.js)
I'm just now noticing that you have a new fullscreen events branch, so maybe this is redundant. No hard feelings if you don't want to use my update. Previously, the player would show the control bar whenever the mouse is hovering over the player, and since the mouse is always hovering over the player while in fullscreen mode, the controls would always be visible then. So I've replaced that with a new method involving mousemove events. To sum up, every time the mouse is moved over the player, the control bar fades in and then a timed event is set to fade out the control bar after 1.5 seconds. I left a lot of comments in the code so there's more explanation in there. Unfortunately I wasn't able to test this in IE8 and below since 3.2.2 seems broken in IE8 and below at the moment, but it seems to work well with everything else.

UPDATED: I fixed a rather obvious shortcoming with yesterday's code: touch devices weren't being accounted for. So I've added a new isTouchDevice() check to lib.js to ensure that non-iOS devices can be tested for, which uses the latest detection from Modernizr (http://stackoverflow.com/questions/4817029/whats-the-best-way-to-detect-a-touch-screen-device-using-javascript) and if that returns true, then the control bar is always shown just like the player's previous behavior for tablets. I've only tested this on an iPad (1st gen) so far but this should work in theory for Android tablets, Windows tablets, etc.

2) Select 'Off' in subtitles menu by default (src/tracks.js)
I thought it was a little weird that nothing in the subtitles menu is selected by default, and that you can then click to select 'Off' if you want but nothing changes. The menu already effectively defaults to 'Off' so this just confirms it.