check out下来后报错提示：
svn: E155036: Please see the 'svn upgrade' command
svn: E155036: Working copy '/home/easwy/dev' is too old (format 10, created by Subversion 1.6)
解决办法：
在命令行下跳转到工程目录文件夹，执行"svn upgrade"命令
svn upgrade
输出：
Upgraded '.'
svn: E155036: Please see the 'svn upgrade' command
svn: E155036: Working copy '/home/easwy/dev' is too old (format 10, created by Subversion 1.6)
svn upgrade
输出：
Upgraded '.'