add yolov6 c++ and yolov6 pybind (#16)

* update .gitignore

* Added checking for cmake include dir

* fixed missing trt_backend option bug when init from trt

* remove un-need data layout and add pre-check for dtype

* changed RGB2BRG to BGR2RGB in ppcls model

* add model_zoo yolov6 c++/python demo

* fixed CMakeLists.txt typos

* update yolov6 cpp/README.md

model_zoo/vision/yolov6/yolov6.py

@@ -0,0 +1,24 @@
+import fastdeploy as fd
+import cv2 
+
+# 下载模型和测试图片
+model_url = "https://github.com/meituan/YOLOv6/releases/download/0.1.0/yolov6s.onnx"
+test_jpg_url = "https://raw.githubusercontent.com/ultralytics/yolov5/master/data/images/bus.jpg"
+fd.download(model_url, ".", show_progress=True)
+fd.download(test_jpg_url, ".", show_progress=True)
+
+# 加载模型
+model = fd.vision.meituan.YOLOv6("yolov6s.onnx")
+print(model.is_dynamic_shape())
+
+# 预测图片
+im = cv2.imread("bus.jpg")
+result = model.predict(im, conf_threshold=0.25, nms_iou_threshold=0.5)
+
+# 可视化结果
+fd.vision.visualize.vis_detection(im, result)
+cv2.imwrite("vis_result.jpg", im)
+
+# 输出预测结果
+print(result)
+print(model.runtime_option)