add Real-ESRGAN training codes

train.py

@@ -0,0 +1,10 @@
+import os.path as osp
+from basicsr.train import train_pipeline
+
+import archs  # noqa: F401
+import data  # noqa: F401
+import models  # noqa: F401
+
+if __name__ == '__main__':
+    root_path = osp.abspath(osp.join(__file__, osp.pardir))
+    train_pipeline(root_path)