[PaddlePaddle Hackathon] Task 72: Add PAA

[gbstack]

PR types

New features

PR changes

APIs

Describe

Hi,

This PR add PAA (Probalistic Anchor Assignment) implementation

[CLAassistant]

Thank you for your submission! We really appreciate it. Like many open source projects, we ask that you all sign our Contributor License Agreement before we can accept your contribution.
4 out of 13 committers have signed the CLA.

✅ nemonameless
✅ jerrywgz
✅ will-jl944
✅ lyuwenyu
❌ heavengate
❌ wangxinxin08
❌ cnn
❌ zhiboniu
❌ YixinKristy
❌ yghstill
❌ ghostxsl
❌ liuhuiCNN
❌ gbstack

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[jerrywgz]

建议向develop分支提交pr，当前改动量太大了

[lyuwenyu]

你好 有模型训练的结果嘛

[gbstack]

你好 有模型训练的结果嘛

你好，目前还没有训练结果，我训练完之后发上来吧

[gbstack]

建议向develop分支提交pr，当前改动量太大了

好的