add xget github acceleration

[jay (yangweijie)]

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add github softawre download acceleration by https://github.com/xixu-me/Xget.git

Closes #XXXX

Relates to #XXXX

[Gabriel Dufresne (GabrielDuf)]

Thanks for the contribution.

After review, we've decided not to move forward with this feature due to security considerations for third-party download acceleration services due to security and trust considerations.

We'll be closing this PR. Thanks again for the contribution and your effort.