[Model] add style transfer model (#922)

* add style transfer model

* add examples for generation model

* add unit test

* add speed comparison

* add speed comparison

* add variable for constant

* add preprocessor and postprocessor

* add preprocessor and postprocessor

* fix

* fix according to review

Co-authored-by: DefTruth <31974251+DefTruth@users.noreply.github.com>

examples/vision/generation/anemigan/python/infer.py

@@ -0,0 +1,43 @@
+import cv2
+import os
+import fastdeploy as fd
+
+
+def parse_arguments():
+    import argparse
+    import ast
+    parser = argparse.ArgumentParser()
+    parser.add_argument("--model", required=True, help="Name of the model.")
+    parser.add_argument(
+        "--image", type=str, required=True, help="Path of test image file.")
+    parser.add_argument(
+        "--device",
+        type=str,
+        default='cpu',
+        help="Type of inference device, support 'cpu' or 'gpu'.")
+    return parser.parse_args()
+
+
+def build_option(args):
+    option = fd.RuntimeOption()
+    if args.device.lower() == "gpu":
+        option.use_gpu()
+    else:
+        option.set_paddle_mkldnn(False)
+    return option
+
+
+args = parse_arguments()
+
+# 配置runtime，加载模型
+runtime_option = build_option(args)
+fd.download_model(name=args.model, path='./', format='paddle')
+model_file = os.path.join(args.model, "model.pdmodel")
+params_file = os.path.join(args.model, "model.pdiparams")
+model = fd.vision.generation.AnimeGAN(
+    model_file, params_file, runtime_option=runtime_option)
+
+# 预测图片并保存结果
+im = cv2.imread(args.image)
+result = model.predict(im)
+cv2.imwrite('style_transfer_result.png', result)