要提交的变更：

	修改：     README.md, 添加文件说明

README.md

@@ -20,6 +20,12 @@ Install these package under Ubuntu 20.04 LTS:
 sudo apt install python3-numpy python3-scipy python3-matplotlib python3-astropy python3-ccdproc
 sudo python3 -m pip install pytorch deepCR
 ```
+#File list
+
+* crmask.py, cosmic ray detection class, it can be either used standalone or imported as a Python module.
+* crmask.ini, configuration file that will be loaded when CRMask class initialized.
+* CSST\_2021-12-30\_CCD23\_epoch20.pth, training models obtained from CSST simulated iimages with 50 hidden layers and 50 epoch.  
+
 # Usage
 
 Download crmask.py and crmask.ini, put them in the same directory.