Optimize for common usage with libp2p

In many cases for the libp2p packages this lib is only used for the cases when N = 1, and the flow is usually "append" -> "sublist" -> "consume". Usually, also, the array only contains 1 element.

So

1). Append
Initialize the empty array in the constructur, and append 1 element to it

2). Sublist
Aquire a sublist which is in many cases just a shallow copy of this array

3). Consume
Make the array empty again

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If this lib instead of utilize an ```linked list``` instead, we could in theory get overall better performance.

1). Append
On appending the first element, the head is set to the first element

2).
A shallow copy

3).
set the head and tail to be undefined

We could do even better, if we combine 2 and 3 into one method called "splice", we can cut the linked list at an appropriate place, which means that we will do much less operations.