refactor: introduct new command line framework

Signed-off-by: Dunrong Huang <riegamaths@gmail.com>
refactor/new: argument parse

Signed-off-by: Dunrong Huang <riegamaths@gmail.com>
refactor/new: write config file

Signed-off-by: Dunrong Huang <riegamaths@gmail.com>
refactor/commands: finish up and down

Signed-off-by: Dunrong Huang <riegamaths@gmail.com>
manager: add list_vm_names

Signed-off-by: Dunrong Huang <riegamaths@gmail.com>
list: add list command

Signed-off-by: Dunrong Huang <riegamaths@gmail.com>
config: dont use bridge virbr0 created by libvirt

Signed-off-by: Dunrong Huang <riegamaths@gmail.com>