增加docker使用描述

README.md

@@ -23,7 +23,18 @@ then
 java -jar JrebelBrainsLicenseServerforJava-1.0-SNAPSHOT-jar-with-dependencies.jar -p 8081
 ```
 default port is 8081.
+## Docker
+Build image
+```
+mvn package 
+docker build -t jrebel-ls .
+```
 
+start container
+```
+docker run -d --name jrebel-ls --restart always -e PORT=9001 -p 9001:9001 jrebel-ls
+```
+default port is 8081,you can modify it
 ## Support
 
 Jrebel