Testr

[wtomin]

Thank you for your contribution to the MindOCR repo.
Before submitting this PR, please make sure:

• You have read the Contributing Guidelines on pull requests
• Your code builds clean without any errors or warnings
• You are using approved terminology
• You have added unit tests

Motivation

• Docs in English and dataset converter classes for four datasets: mlt2017, totaltext, syntext2015, ic15.
• Unittest for the four datasets.
• A shell script to automatically convert all existing datasets.
• requirements include addict

Test Plan

Run tests/convert/test_dataset_converters.py

Related Issues and PRs

Not related.

[SamitHuang]

Please merge the 35 commits into one commits for code clean.

[wtomin]

The history and commits now seem correct to me.