Dftt-timecode

添加 Add:
- `__str__`方法,返回DfttTimecode对象的时间码值

`__str__`method,return timecode value for DfttTimecode object

- DfttTimecode单元测试(使用pytest)

Unit test for DfttTimecode (Using pytest)

修改 Modify：
- 对丢帧的检测条件添加有关23.98/23.976的判定

Add 23.98/23.976FPS to drop frame conditions

- `+` `-`运算符对相加的两个DfttTimecode对象的strict属性进行或运算

`+` `-`operators performs an or operation on the strict property of two DfttTimecode objects that are added together

- 比较运算符,比如`==` `>` `>=`等,在对两个DfttTimecode对象进行比较的时候会先对两个对象的帧率进行判定,若帧率不同抛出异常

Comparison operators, such as `==`, `>`, `>=`, in the comparison of two DfttTimecode objects will first compare the frame rate of the two objects, if the frame rate is different throw an exception

- `print(self)` 将会输出基于类型的时间码字符串

`print(self)` will output a timecode string

修复 BugFix:
- `timecode_output(self, dest_type, output_part)` 中`output_part = 3`时错误返回分钟数据的问题

Addressed a problem when `output_part = 3` in `timecode_output(self, dest_type, output_part)` would return minute value in timecode value

V0.0.12
修复 BugFix:
- 修复DLP正则表达式错误导致范围在50-99 150-199的DLP tick不能被匹配的问题。
这一bug会导致使用形如`'00:00:27:183'`的字符串初始化dlp时间码对象时的报错。

Fix DLP pattern error causing DLP ticks range [50-99] [150-199] cannot be matched.
This bug will cause error when using strings like `'00:00:27:183'` to initilize a dlp timecode object.

添加 Add:

- 使用DfttTimecode对象初始化新DfttTimecode对象

Using a DfttTimecode object to instance a new DfttTimecode object.

- DfttTimecode类的float和int方法

class method float() and int() for DfttTimecode class

- DfttTimecode类的precise_timestamp属性

attribute precise_timestamp for class DfttTimecode

修改 Modify：

- DfttTimecode运算符在未定义/非法操作时将会报错

Will raise an error when DfttTimecode operators meet undefined circumstances or illegal operations.

- DfttTimecode运算符的大小比较规则

Compare functions of DfttTimecode operators.

- 使用SMPTE NDF格式字符串新建时码类对象时，若强制drop_frame为True，则新建得到的对象为SMPTE DF格式时码

First Public Release.