Add jail icons and modify system to use them

- Create new icon selectors in FreeNAS CSS file

- Pass gname to openjails() javascript function

- Turn off ability to sort jails by attribute since it does not work

- Implement jails model order_by() method

- Configure navtree to use new jail icons

- Shorten view for jails configuration

- Switch to proper tab in jails view

- Use new jail icon in menubar

- Use plugin icon on plugins page

- Use storage icon on plugins page