resolves #1540

• Updates the increments for the playback speed to be [0.25, 0.5, 0.75, 1.0, 1.5, 2.0, 2.5, 3.0, 3.5, 4.0, 5.0, 6.0, 7.0, 8.0]
• This required restructuring and not having the ticks be displayed for each value. Instead the value is displayed at the bottom of the popup.
• 
• Still has the default behavior where clicking the playback speed will reset it back to 1.0
• Also updated the volume to include the Percentage level of the volume when being changed.