Add all the elements of aCollection after the one at index anIndex. If
aCollection is unordered, its elements could be added in an order which is
not the #do: order
addAllFirst: aCollection
Add all the elements of aCollection at the beginning of the receiver. If
aCollection is unordered, its elements could be added in an order which is
not the #do: order
addAllLast: aCollection
Add all the elements of aCollection at the end of the receiver. If aCol-
lection is unordered, its elements could be added in an order which is not
the #do: order
addFirst: anObject
Add anObject at the beginning of the receiver. Watch out: this operation
can cause serious performance pitfalls