Music controls
The first 4 images are composed of 3 images each one and they have the same names except that if they have no suffix is the normal icon, if they have as suffix "_p" is the image when it is pressed and if they have as suffix "_d" is that the button is deactivated.
Their names are:
* "MCPlay~iphone.png" ("MCPlay~ipad.png")
* "MCPause~iphone.png" ("MCPause~ipad.png")
* "MCNext~iphone.png" ("MCNext~ipad.png")
* "MCPrev~iphone.png" ("MCPrev~ipad.png").
And for AirPlay icons they are 4 images called:
* "SwitcherAirPlayNowPlayingButton~iphone.png" ("SwitcherAirPlayNowPlayingButton~ipad.png"): it's the normal icon.
* Adding the suffix "Pressed": it's the icon when it is pressed.
* Adding the suffix "On": it's the icon when it is activated.
* Adding the suffix "OnPressed": it's the icon when it is activated and pressed.
The size of all these images is 47x47 px (61x61 px)
NOTE: suffixes are added before @2x~iphone or ~ipad.
