fix #713 Slider widgets improvement (touch library)



Changes done:

 - Slider and DoubleSlider have the same CSS class name, so there are conflicts when used in the same page
-> Renamed CSS class of DoubleSlider  to touchLibDoubleSlider
 - Both do not accept the standard attributes option, e.g attributes: { classList: ["switch"] },
-> In both widgets, used aria.utils.Html.buildAttributeList to generate attribute list
 - tapToMove option does not work in Slider
-> Changed the behavior so that taping the bar actually moves the button to the tap position. In switch mode, tapToMove is now the same as tapToToggle
 - Switch labels should be definable by users, instead of being hardcoded to ON and OFF
-> Added options in Slider to define the labels
 - Highlight bar in DoubleSlider is not well filling the space when the buttons are round
-> Changed highlight bar width to reach the center of the buttons
 - Highlight bar should also available in Slider
-> Added a highlight bar when the Slider is not a switch
 - bindValue discrepancy
-> In DoubleSlider, changed bindValue to bind: {value: ...}