Function maskChineseName

maskChineseName(text?: string | null): string | undefined
Returns a masked Chinese name, which keeps the surname only

The surname is kept as 2 characters for the common compound surnames, otherwise 1 character. For minority names separated by the middle dot, each segment is masked individually
Parameters
- Optionaltext: string | null
  The text to mask
Returns string | undefined
a masked Chinese name, or undefined if the given text is invalid
Author
David Hsing
Example
```
maskChineseName(undefined);    // undefined
maskChineseName('张三');    // '张*'
maskChineseName('张三丰');    // '张**'
maskChineseName('欧阳修');    // '欧阳*'
maskChineseName('欧阳修文');    // '欧阳**'
maskChineseName('阿依古丽·买买提');    // '阿***·买**'
maskChineseName('Tom');    // undefined
```