* Add Pascal Context to mmsegmentation

* Add benchmark result to Pascal Context

* fix mmcv version

* fix code syntax

* fix code syntax again

* Update mmseg/models/segmentors/encoder_decoder.py

update hint

Co-authored-by: Jerry Jiarui XU <xvjiarui0826@gmail.com>

* update comment

* fix pascal context model path

* fix model path mistake again

* fix model path mistake again

* fix model path mistakes again

Co-authored-by: Jerry Jiarui XU <xvjiarui0826@gmail.com>

* add pytorch2onnx part

* Update according to the latest mmcv

* add docstring

* update docs

* update docs

Co-authored-by: Jiarui XU <xvjiarui0826@gmail.com>