fixed, case insensitive matching

lxc version: 1.0.0.alpha3
$ sudo lxc-info -n test_default-1387877096
Name:           test_default-1387877096
State:          RUNNING
....
Merge branch 'release/0.7.0.1'
Merge branch 'master' of https://github.com/hiono/vagrant-lxc into next

Conflicts:
	lib/vagrant-lxc/driver/cli.rb