Flexible widths

[jmkenz]

~changed -vuedal width set to 95% and width options changed to use 'max-width' property instead of 'width' to support responsive design -close button is a keyboard-accessible / semantic 'a' tag instead of 'span'

~notes -Automatically moving keyboard focus to the veudal when it opens can be done through a callback function that runs in response to the 'opened' bus event. Consider baking this functionality right into this lib.