Update README.md (pytorch#85534)

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Pull Request resolved: pytorch#85534
Approved by: https://github.com/ngimel, https://github.com/kit1980

caffe2/README.md

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 # Caffe2
 
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 Caffe2 is a lightweight, modular, and scalable deep learning framework. Building on the original [Caffe](http://caffe.berkeleyvision.org), Caffe2 is designed with expression, speed, and modularity in mind.
 
 ## Questions and Feedback