增加dockerfile文件，完善webapi.py功能

解决webapi.py运行时报错的bug

Bump flask from 0.12.4 to 1.0 in /hyperlpr_py3

Bump tensorflow from 1.13.2 to 1.15.2 in /hyperlpr_py3

Bumps [flask](https://github.com/pallets/flask) from 0.12.4 to 1.0.
- [Release notes](https://github.com/pallets/flask/releases)
- [Changelog](https://github.com/pallets/flask/blob/master/CHANGES.rst)
- [Commits](https://github.com/pallets/flask/compare/0.12.4...1.0)

Signed-off-by: dependabot[bot] <support@github.com>

Bumps [tensorflow](https://github.com/tensorflow/tensorflow) from 1.13.2 to 1.15.2.
- [Release notes](https://github.com/tensorflow/tensorflow/releases)
- [Changelog](https://github.com/tensorflow/tensorflow/blob/master/RELEASE.md)
- [Commits](https://github.com/tensorflow/tensorflow/compare/v1.13.2...v1.15.2)

Signed-off-by: dependabot[bot] <support@github.com>

解决Android10下有文件访问权限但读取模型还是失败的问题。

Merge pull request #1 from zeusees/master

* 'master' of https://github.com/zeusees/HyperLPR:
  Update README.md