Checkboxradio: Updated CSS.
Theme: Deprecated in 1.4 comment for ui-btn-corner-all.
Grids: Reduced CSS.
Button: Optimized CSS for button elements.
Grid: Only make grids responsive when class ui-responsive is added to the grid container.

This matches the documentation and pevents conflicts with widgets that also repond to this class.
Grid: Make it easy to use grids to layout unordered lists.
Button: Don't add class ui-btn-hidden to native inputs but use a type selector.
Button: Only unset the margin in grids for 100% width button elements.
Grid: Removed "immediate child" from selector.

It's not really needed and this way you can wrap a row in a <form> for example.
Demos: Updated grid and buttons in grids demo pages.
Select: Removed ui-btn-inner from CSS.