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[x] The PR title starts with [new] (例如[bugfix]修复bug，[new]添加新功能，[test]修改测试，[rm]删除旧代码)
[x] Changes are complete (i.e. I finished coding on this PR) 修改完成才提PR
[x] All changes have test coverage 修改的部分顺利通过测试。对于fastnlp/fastnlp/的修改，测试代码必须提供在fastnlp/test/。
[ ] Code is well-documented 注释写好，API文档会从注释中抽取，只写了模型的部分
[ ] To the my best knowledge, examples are either not affected by this change, or have been fixed to be compatible with this change 修改导致例子或tutorial有变化，请找核心开发人员
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添加了新模型；实现了Jie Yang的Chinese NER Using Lattice LSTM，能够在weibo和resume数据集上明显超过原文报告的性能，在ontonote上差原文报告性能0.3个点
Description：实现支持batch并行的lattice lstm
Main reason: 实现支持batch并行的lattice lstm
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