openmediavault 的 extra插件包安装方法，均为3行代码：
For OMV 2.x (stoneburner)
wget http://omv-extras.org/openmediavault-omvextrasorg_latest_all.deb
dpkg -i openmediavault-omvextrasorg_latest_all.deb
apt-get update
For OMV 3.x (erasmus) (STILL BETA)
wget http://omv-extras.org/openmediavault-omvextrasorg_latest_all3.deb
dpkg -i openmediavault-omvextrasorg_latest_all3.deb
apt-get update