modified dockerfile and jenkins file for CI

Dockerfile

@@ -4,7 +4,7 @@
 #####
 
 # Set the base image to Ubuntu
-FROM Ubuntu
+FROM ubuntu
 # File Author / Maintainer
 # MAINTAINER name Chunteng Xiao
 

Jenkinsfile

@@ -3,6 +3,7 @@ pipeline {
         dockerfile {
             filename 'Dockerfile'
             customWorkspace '/usr/bi-web'
+            registryUrl 'https://registry.docker-cn.com'
             args '-p 80:80'
         }
     }