3 Array#splice tests failing in IE 8

[ljharb]

These tests pass just fine in IE 6 and 7.

Relates to #114.

[Xotic750]

This was one persons study and conclusions.
https://social.msdn.microsoft.com/Forums/ie/en-US/6e946d03-e09f-4b22-a4dd-cd5e276bf05a/splice-function-in-ie8-is-broken?forum=iewebdevelopment

Also, IE <9 has a bug/difference where the second argument is required rather than optional. I don't think you have any tests for this?

var array = [0, 1, 2];
array.splice(0);
alert(array);

http://stackoverflow.com/questions/8332969/ie-8-splice-not-working

So, it looks like 2 tests and fixes.

IE8 should just use the full replacement, I don't think you can do a partial reasonably?

IE<8 requires a partial for the second argument, when it is not supplied.