linux添加环境变量
参考：
https://www.cnblogs.com/toward-the-sun/p/8030238.html
export PATH=$PATH:/opt/software/node-v8.9.3-linux-x64/bin/node
//2,修改配置文件/etc/profile
vi /etc/profile
在里面加入:export PATH=$PATH:/opt/software/node-v8.9.3-linux-x64/bin/node
参考：
https://www.cnblogs.com/toward-the-sun/p/8030238.html
export PATH=$PATH:/opt/software/node-v8.9.3-linux-x64/bin/node
//2,修改配置文件/etc/profile
vi /etc/profile
在里面加入:export PATH=$PATH:/opt/software/node-v8.9.3-linux-x64/bin/node