before the following would produce four entries:
container_config:
- "lxc.network.flags=up"
- "lxc.network.flags =up"
- "lxc.network.flags= up"
- "lxc.network.flags = up"
let's strip the whitespace and insert only one "lxc.network.flags = up"
into the final config
Signed-off-by: Evgeni Golov <evgeni@golov.de>