Funccache

1. Fix a critical error.
2. Improve a few type annotations.
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1. 修复一个严重的错误。
2. 改进少量类型注解。

What's Changed
* 2.0.4 by 2018-11-27 in https://github.com/gqylpy/funccache/pull/11


**Full Changelog**: https://github.com/gqylpy/funccache/compare/2.0.3...2.0.4

1. Fix the potential errors that may occur in the class cache when running in performance mode.
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1. 修复在性能模式下运行时类缓存器可能发生的错误。

1. Correct a consecutive judgment error in the code.
2. Refactor the internal method `Time2Second` to make it more concise and efficient.
3. Use `time.monotonic()` to replace `time.time()` for cache expiration checks.
4. Adjust the formatting and annotations of other minor code sections.
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1. 修正代码中的一个连续判断错误。
2. 重构内部方法 `Time2Second` 使之更简洁和高效。
3. 使用 `time.monotonic()` 替换 `time.time()` 进行缓存过期检查。
4. 调整其它少量代码格式和注解。

What's Changed
* 2.0.2 by 2018-11-27 in https://github.com/gqylpy/funccache/pull/8


**Full Changelog**: https://github.com/gqylpy/funccache/compare/2.0.1...2.0.2

1. A small amount of code optimization.
2. Correct the Chinese document link.
3. Correct the brief description information on PyPi.

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1. 少量的代码优化。
2. 更正中文文档链接。
3. 更正在 PyPi 上的简述信息。