Missing methods in ArrayBufferView

[Schahen]

Following methods are missing from Uint8Array (and other ArrayBufferView implementations for that matter):

fun slice(begin: Int, end: Int): Uint8Array 
fun subarray(begin: Int, end: Int): Uint8Array 
fun reverse(): Uint8Array 

// following signature yet to figure out
fun entries(): IterableIterator<dynamic /* JsTuple<Number, Number> */>
fun keys(): IterableIterator<Number>
fun values(): IterableIterator<Number>