Teste:

# dpkg -l linux-* | awk '/^ii/{ print $2}' | grep -v -e `uname -r | cut -f1,2 -d"-"` | grep -e [0-9] | grep -E "(image|headers)" | xargs sudo apt-get --dry-run remove

Efetivo:

# dpkg -l linux-* | awk '/^ii/{ print $2}' | grep -v -e `uname -r | cut -f1,2 -d"-"` | grep -e [0-9] | grep -E "(image|headers)" | xargs sudo apt-get -y purge

Testado no Ubuntu 14.04.

Mover do /var/lib para o /home :

# service mysql stop
# mv /var/lib/mysql /home
# ln -s /home/mysql /var/lib/mysql

Editar o arquivo /etc/apparmor.d/tunables/alias, e descomentar a linha abaixo:

alias /var/lib/mysql/ -> /home/mysql/,

Reiniciar os serviços:

# service apparmor restart
# service mysql start

# export LANG=C; do-release-upgrade