Off by one error in replace

[notquiteamonad]

My understanding of the replace function on BackStack is that it should swap the item at the top of the stack, so if the routing is a,b,c and replace(d) is called it should become a,b,d.

However, the replace function uses .subList(0, elements.lastIndex - 1) which removes 2 elements (the second argument being exclusive).

This should probably either change to use size or remove the -1 (the latter makes more sense to me).

This is, of course, all invalid if I've misunderstood what replace is supposed to do.

[zsoltk]

Thanks @samueldple! Released fix as 0.13.1