Bug fixes and docs improvements

PyTorch-Ignite 0.4.4 - Release Notes

Bug fixes:

• BC-breaking Moved detach outside of loss function computation (#1675, #1692)
• Added eps to avoid nans in canberra error (#1699)
• Removed size limitation for str on collective ops (#1702)
• Fixed imports in docker images and now install Pillow-SIMD (#1638, #1639, #1628, #1711)

Doc improvements

• #1645, #1653, #1654, #1671, #1672, #1691, #1687, #1686, #1685, #1684, #1676, #1688

Other improvements

• Fixed artifacts urls for pypi (#1629)

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Acknowledgments

🎉 Thanks to our community and all our contributors for the issues, PRs and 🌟 ⭐️ 🌟 !
💯 We really appreciate your implication into the project (in alphabetical order):

@Devanshu24, @KickItLikeShika, @Moh-Yakoub, @OBITORASU, @ahmedo42, @fco-dv, @sparkingdark, @touqir14, @trsvchn, @vfdev-5, @y0ast, @ydcjeff