Add bind mounting in /etc/fstab to prevent mount timing error

The VirtualBox drive was mounted before the remounting of /var occurred,
resulting in the mount being lost. This change puts the bind mounts into
/etc/fstab where they can occur before the VirtualBox drive is mounted, with
the remounting for nosuid happening later in the karoshi-remount Upstart
script
Merge branch 'master' into develop
Modify set-network to correctly do wireless, fixes #40
Fix wrong command to add bind mounts to fstab
Add checks to make sure directories *are* mountpoints
Modify window behaviour (such as snapping)
Use new squid-deb-proxy for APT proxy
Add 'screen' to install list
Sleep a little while waiting for the interface to be up
Prevent Thunderbird downloading everything, change sort order

Thunderbird will now sort by descending date, which is How It Should Be (TM)
Fix broken parts in wireless setup

Turns out you can't run 'timeout' on a Bash function...
Wait for network before booting