Quick pass on all translations.

* Some markup fixes and unify.
* Fix punctuations.
* Remove unnecessary things.
* Use https when possible

Ref: #65 
> 你說說的一致性是跟哪邊一致？

每章最後都有

```
      <div class="verify">
        <h3>確認你完成了所有步驟：</h3><code>git-it verify</code>
        <h3>前往下一關：</h3><code>git-it</code>
      </div>
```