vim7爆出严重安全漏洞，升级到vim8，过程如下：
yum remove vim -y
yum install ncurses-devel -y
如果失败，提示unknown host apt.sw.be，手工安装：
wget http://mirror.centos.org/centos/7/os/x86_64/Packages/ncurses-devel-5.9-13.20130511.el7.x86_64.rpm
yum install ncurses-devel-5.9-13.20130511.el7.x86_64.rpm
git clone https://github.com/vim/vim.git
cd vim/src
make
make install
编辑文件：
/usr/local/bin/vim /etc/profile.d/path.sh
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#!/bin/bash
export PATH=$PATH:/usr/local/bin/vim
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source /etc/profile.d/path.sh
vim