Explode from end with negative limit

Description

I would find more consistent explode if negative limit will return N parts from the end like positive limit does from start. For limitting the actual additional param should be added. This will be consistent with other functions with negative limit.

repro: https://3v4l.org/u9WM3

Array
(
    [0] => a
    [1] => b-c-d
)
Array
(
    [0] => a-b-c
    [1] => d
)

从 issue 中展示的 PHP explode 行为开始，使用链接的 3v4l.org 复现来比较正数 limit 和负数 limit 的情况。确定从末尾进行限制的预期 API，并添加用于展示预期结果的覆盖测试，然后再评估解释器的更改。