add scrubber animation on drag
add scrubber animation on drag

xuvw/clappr-ios,clappr/clappr-ios,xuvw/clappr-ios,barbosa/clappr-ios,barbosa/clappr-ios,clappr/clappr-ios,xuvw/clappr-ios,xuvw/clappr-ios,clappr/clappr-ios