[TIMOB-4123] iOS: Label height set to auto should return "auto" for Android parity.

Description: Setting label.height to 'auto' then reading the height value returns "2". This bug was originally in the Android component as TIMOB-3202 and was fixed (set to return 'auto'). For parity, iOS should follow suit. steps to reproduce: 1) Create sample app and replace app.js with: var win = Titanium.UI.createWindow({ backgroundColor:'white' }); win.open(); var label = Ti.UI.createLabel(); label.height = 'auto'; alert('Label height is: '+label.height); 2) launch the app Result: The alert reports "2" Expected: The alert reports "auto" (for android parity)