add M2Det official code

Author: hoya012

README.md

@@ -1,7 +1,7 @@
 # deep learning object detection
 A paper list of object detection using deep learning. I worte this page with reference to [this survey paper](https://arxiv.org/pdf/1809.02165v1.pdf) and searching and searching.. 
 
-*Last updated: 2019/03/05*
+*Last updated: 2019/03/18*
 
 #### Update log
 *2018/9/18* - update all of recent papers and make some diagram about history of object detection using deep learning. 
@@ -11,7 +11,7 @@ A paper list of object detection using deep learning. I worte this page with ref
 *2018/december* - update 8 papers and and performance table and add new diagram(**2019 version!!**).  
 *2019/january* - update 4 papers and and add commonly used datasets.  
 *2019/february* - update 3 papers.  
-*2019/march* - update figure.
+*2019/march* - update figure and code links.
 
 
 ##
@@ -238,7 +238,7 @@ FPS(Speed) index is related to the hardware spec(e.g. CPU, GPU, RAM, etc), so it
 - **[SNIPER]** SNIPER: Efficient Multi-Scale Training | Bharat Singh, et al. | **[NIPS' 18]** |[`[pdf]`](http://papers.nips.cc/paper/8143-sniper-efficient-multi-scale-training.pdf) 
 
 ## 2019
-- **[M2Det]** M2Det: A Single-Shot Object Detector based on Multi-Level Feature Pyramid Network | Qijie Zhao, et al. | **[AAAI' 19]** |[`[pdf]`](https://arxiv.org/pdf/1811.04533.pdf) 
+- **[M2Det]** M2Det: A Single-Shot Object Detector based on Multi-Level Feature Pyramid Network | Qijie Zhao, et al. | **[AAAI' 19]** |[`[pdf]`](https://arxiv.org/pdf/1811.04533.pdf) [`[official code - pytorch]`](https://github.com/qijiezhao/M2Det)
 
 - **[R-DAD]** Object Detection based on Region Decomposition and Assembly | Seung-Hwan Bae | **[AAAI' 19]** |[`[pdf]`](https://arxiv.org/pdf/1901.08225v1.pdf)