refactor: smaller package size

[qmhc]

在这个 PR 中我做了一些改进，以及一些自作主张的调整。

• 改变了运算方法的创建方式，采用了一个构造方法来创建运算方法，并在这个过程中使用循环取代了递归
• 将所有的方法的注释改为了英语，并补全了参数说明

首先关于第一点，我实施它是因为可以使得压缩 gzip 后包变得更小了：

之前：

之后：

同时在效率上能够有微弱的提升：

function test() {
  let times = 0
  for (let i = 0; i < 10; ++i) {
    let start = Date.now()
    NP.plus(...new Array(120000).fill(1))
    times += Date.now() - start
  }
  console.log(times / 10)
}

在 Chrome 下运行数次，递归方案平均时长约在 242ms，循环方案时长约在 235ms，不过这个性能差异在正常的使用中我觉得几乎没影响。

第二点是我自作主张的调整，我认为全面的参数说明和英语能够更广泛的适应更多用户，如果你不喜欢这样的调整，我可以撤回。

[codecov]

Codecov Report

Base: 96.82% // Head: 94.87% // Decreases project coverage by -1.95% ⚠️

Coverage data is based on head (973458c) compared to base (e516fed).
Patch coverage: 94.44% of modified lines in pull request are covered.

❗ Current head 973458c differs from pull request most recent head a49a973. Consider uploading reports for the commit a49a973 to get more accurate results

Additional details and impacted files

@@            Coverage Diff             @@
##           master      #50      +/-   ##
==========================================
- Coverage   96.82%   94.87%   -1.96%     
==========================================
  Files           1        1              
  Lines          63       78      +15     
  Branches       13       13              
==========================================
+ Hits           61       74      +13     
- Misses          2        4       +2     

Impacted Files	Coverage Δ
src/index.ts	94.87% <94.44%> (-1.96%)	⬇️

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[camsong]

I like this idea very much, better to use array#reduce:

let [first, ...others] = numbers;
return others.reduce((prev, next) => operation(prev, next), first) as number;