adding mobilenetv2 to docs/model_zoo.md and readme.md (open-mmlab#146)

* updating the readme with mobilenet_v2 backbone

* adding mobilenetv2 to model_zoo.md

* placing mobilenetv2 after pointrend

Author: ZidanMusk

README.md

@@ -56,6 +56,7 @@ Supported backbones:
 - [x] ResNeXt
 - [x] [HRNet](configs/hrnet/README.md)
 - [x] [ResNeSt](configs/resnest/README.md)
+- [x] [MobileNetV2](configs/mobilenet_v2/README.md)
 
 Supported methods:
 - [x] [FCN](configs/fcn)

docs/model_zoo.md

@@ -97,6 +97,10 @@ Please refer to [Semantic FPN](https://github.com/open-mmlab/mmsegmentation/blob
 
 Please refer to [PointRend](https://github.com/open-mmlab/mmsegmentation/blob/master/configs/point_rend) for details.
 
+### MobileNetV2
+
+Please refer to [MobileNetV2](https://github.com/open-mmlab/mmsegmentation/blob/master/configs/mobilenet_v2) for details.
+
 ### EMANet
 
 Please refer to [EMANet](https://github.com/open-mmlab/mmsegmentation/blob/master/configs/emanet) for details.