add box_iou_rotated, ml_nms_rotated and nms_rotated

[magicdream2222]

add box_iou_rotated, ml_nms_rotated and nms_rotated ops for pytorch and parrots.

[codecov]

Codecov Report

Merging #625 (c68939c) into master (c8146cc) will increase coverage by 0.22%.
The diff coverage is 48.73%.

@@            Coverage Diff             @@
##           master     #625      +/-   ##
==========================================
+ Coverage   64.61%   64.84%   +0.22%     
==========================================
  Files         134      135       +1     
  Lines        7672     7830     +158     
  Branches     1358     1387      +29     
==========================================
+ Hits         4957     5077     +120     
- Misses       2459     2488      +29     
- Partials      256      265       +9     

Flag	Coverage Δ
unittests	64.84% <48.73%> (+0.22%)	⬆️

Flags with carried forward coverage won't be shown. Click here to find out more.

Impacted Files	Coverage Δ
mmcv/cnn/__init__.py	100.00% <ø> (ø)
mmcv/cnn/bricks/conv_module.py	100.00% <ø> (ø)
mmcv/cnn/bricks/depthwise_separable_conv_module.py	100.00% <ø> (ø)
mmcv/image/__init__.py	100.00% <ø> (ø)
mmcv/ops/modulated_deform_conv.py	50.44% <ø> (ø)
mmcv/ops/roi_pool.py	43.90% <ø> (ø)
mmcv/runner/epoch_based_runner.py	79.04% <0.00%> (ø)
mmcv/runner/hooks/logger/tensorboard.py	35.48% <0.00%> (+10.48%)	⬆️
mmcv/runner/hooks/optimizer.py	25.00% <5.26%> (-2.54%)	⬇️
mmcv/ops/roi_align.py	61.33% <9.09%> (-2.73%)	⬇️
... and 25 more

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[Johnson-Wang]

Please add necessary docstrings to the ops

[CLAassistant]

All committers have signed the CLA.

[Johnson-Wang]

Please kindly sign the CLA.

[Johnson-Wang]

As discussed earlier, multi_label can be safely deleted for the purpose of clearer code structure in cuda files.

[magicdream2222]

ok啦 @Johnson-Wang